The role of the cervical spine in post-concussion syndrome

Clinical Changes in Cervical Neuromuscular Control Following Subconcussive Impacts

CONTEXT

Increased injury rates following concussive injury have been attributed to decreased neuromuscular coordination frequently documented following a concussion. However, altered integration between the vestibular system and oculomotor pathways following impacts at subconcussive thresholds implicate all sports-related impacts not just those at a concussive threshold in future musculoskeletal injury. While, several studies have explored the utility of vestibular and oculomotor clinical testing to detect altered neuromuscular control and then correlated those alterations to future injury risk, no research has explored the use of cervical clinical tests in the same capacity.

OUTCOME MEASURES

Cervical joint position error test, Neck Disability Index and head acceleration.

INTERVENTIONS

Soccer headers, fatigue protocol, soccer headers + fatigue.

OBJECTIVE

To explore the clinical utility of a novel clinical approach to measuring changes in cervical neuromuscular control following subconcussive impacts in a controlled lab environment.

PARTICIPANTS

40 current female colligate club soccer athletes were recruited. Inclusion criteria included between the age of 18 and 25 and a minimum of 4-year soccer heading experience.

SETTING

Laboratory.  Design: A repeated-measures design with 4 groups was utilized to test the hypothesis.

RESULTS

A 65%, 54%, and 49% increased error was observed following the soccer heading, fatigue only, and soccer heading + fatigue interventions, respectively. Meanwhile, the controls saw a 6% decrease in neck position error. Concussion: While, cervical joint position error testing was sensitive to decreased neuromuscular coordination following soccer heading, it was not specific enough to rule out an exercise effect in the absence of subconcussive impacts. Further research is warranted to explore the clinical utility and specificity of cervical joint position error testing to measured alterations in supraspinal processing following subconcussive impacts, and how these alterations may lead to decreased coordination and movement of the body during sports-related task.

Post-traumatic cephalalgia

After traumatic brain injury (TBI), a host of symptoms of varying severity and associated functional impairment may occur. One of the most commonly encountered and challenging to treat are the post-traumatic cephalalgias. Post-traumatic cephalalgia (PTC) or headache is often conceptualized as a single entity as currently classified using the ICHD-3. Yet, the terminology applicable to the major primary, non-traumatic, headache disorders such as migraine, tension headache, and cervicogenic headache are often used to specify the specific type of headache the patients experiences seemingly disparate from the unitary definition of post-traumatic headache adopted by ICHD-3. More complex post-traumatic presentations attributable to brain injury as well as other headache conditions are important to consider as well as other causes such as medication overuse headache and medication induced headache. Treatment of any post-traumatic cephalalgia must be optimized by understanding that there may be more than one headache pain generator, that comorbid traumatic problems may contribute to the pain presentation and that pre-existing conditions could impact both symptom complaint, clinical presentation and recovery. Any treatment for PTC must harmonize with ongoing medical and psychosocial aspects of recovery.

Practical Management: Brief Physical Examination for Sport-Related Concussion in the Outpatient Setting

This article presents a brief, focused physical examination [PE, the Buffalo Concussion Physical Examination (BCPE)] for sport-related concussion (SRC) to be considered for use in the outpatient setting by sports medicine physicians, pediatricians, and primary-care physicians. This companion paper describes how to perform the PE, which was derived in a separate study presented in this journal. It is envisioned for use at the initial and follow-up outpatient visits both for acute concussions and in patients with prolonged symptoms. A pertinent PE, combined with other assessments, can help identify specific treatment targets in those with persistent symptoms after SRC. The BCPE includes orthostatic vital signs and examinations of the cranial nerves, oculomotor/ophthalmologic, cervical, and vestibular systems. Supplementary tests, including testing for exercise tolerance and neurocognitive function, may be performed if indicated. It is recommended that a PE be performed at the initial visit and every 1 to 2 weeks after SRC. On return of symptoms, cognition, and the PE to baseline, as well as normalization of any supplementary tests, patients can begin a return to play program.

Patients with mild traumatic brain injury and acute neck pain at the emergency department are a distinct category within the mTBI spectrum: a prospective multicentre cohort study

BACKGROUND

Acute neck pain (ANP) has recently been demonstrated to be a predictor of persistent posttraumatic complaints after mild traumatic brain injury (mTBI). The aim of this study was to determine specific characteristics of patients with ANP following mTBI, their posttraumatic complaints and relationship with functional outcome.

METHODS

Data from a prospective follow-up study of 922 mTBI patients admitted to the emergency department (ED) in three level-one trauma centres were analysed. Patients were divided into two groups: 156 ANP patients and 766 no acute neck pain (nANP) patients. Posttraumatic complaints were evaluated 2 weeks and 6 months post-injury using standardized questionnaires and functional outcome was evaluated at 6 months with the Glasgow Outcome Scale Extended (GOSE).

RESULTS

ANP patients were more often female (p < 0.01), younger (38 vs. 47 years, p < 0.01) with more associated acute symptoms at the ED (p < 0.05) compared to nANP patients. More motor vehicle accidents (12% vs. 6%, p = 0.01) and less head wounds (58% vs. 73%, p < 0.01) in ANP patients indicated 'high-energy low-impact' trauma mechanisms. ANP patients showed more posttraumatic complaints 2 weeks and 6 months post-injury (p < 0.05) and more often incomplete recovery (GOSE < 8) was present after 6 months (56% vs. 40%, p = 0.01).

CONCLUSIONS

MTBI patients with acute neck pain at the ED constitute a distinct group within the mTBI spectrum with specific injury and demographic characteristics. Early identification of this at risk group already at the ED might allow specific and timely treatment to avoid development of incomplete recovery.

White Matter Integrity and Its Relationship to Cognitive-Motor Integration in Females with and without Post-Concussion Syndrome

Fifteen percent of individuals who sustain a concussion go on to develop post-concussion syndrome (PCS). These persistent symptoms are believed to be attributed to damage to white matter tracts and impaired neurotransmission. Specifically, declines in white matter integrity after concussion have been found along the long-coursing axons underlying the frontoparietal network. This network is essential for the performance of visuomotor transformation tasks requiring cognitive-motor integration (CMI). We have previously observed deficits in performance on CMI-based tasks in those who have a history of concussion, but were asymptomatic. The aim of this study was to investigate performance on a CMI task, as well as white matter integrity differences along frontoparietal-cerebellar white matter tracts, in those with PCS compared to healthy controls. We hypothesized an association between the behavioral and brain structural measures. Twenty-six female participants (13 with PCS for ≥6 months and 13 healthy controls) completed four computer-based visuomotor CMI tasks. In addition, diffusion tensor images (DTIs) were acquired. No statistically significant differences were found in CMI performance between groups (p > 0.05). Further, there were no statistically significant differences between groups on any DTI metrics (p > 0.05). However, examination of the data collapsed across participants revealed significant associations between performance on a CMI task and white matter integrity. Further investigation into additional causes of symptoms in those with PCS (including psychological and cervicogenic factors) will strengthen our understanding of this diverse group. Nonetheless, this study demonstrates that white matter integrity is related to levels of performance in tasks that require rule-based movement control.

Physical Therapy Evaluation and Treatment After Concussion/Mild Traumatic Brain Injury

Over the last decade, numerous concussion evidence-based clinical practice guidelines (CPGs), consensus statements, and clinical guidance documents have been published. These documents have typically focused on the diagnosis of concussion and medical management of individuals post concussion, but provide little specific guidance for physical therapy management of concussion and its associated impairments. Further, many of these guidance documents have targeted specific populations in specific care contexts. The primary purpose of this CPG is to provide a set of evidence-based recommendations for physical therapist management of the wide spectrum of patients who have experienced a concussive event. J Orthop Sports Phys Ther 2020;50(4):CPG1-CPG73. doi:10.2519/jospt.2020.0301.

Concussion Guidelines Step 2: Evidence for Subtype Classification

BACKGROUND

Concussion is a heterogeneous mild traumatic brain injury (mTBI) characterized by a variety of symptoms, clinical presentations, and recovery trajectories. By thematically classifying the most common concussive clinical presentations into concussion subtypes (cognitive, ocular-motor, headache/migraine, vestibular, and anxiety/mood) and associated conditions (cervical strain and sleep disturbance), we derive useful definitions amenable to future targeted treatments.

OBJECTIVE

To use evidence-based methodology to characterize the 5 concussion subtypes and 2 associated conditions and report their prevalence in acute concussion patients as compared to baseline or controls within 3 d of injury.

METHODS

A multidisciplinary expert workgroup was established to define the most common concussion subtypes and their associated conditions and select clinical questions related to prevalence and recovery. A literature search was conducted from January 1, 1990 to November 1, 2017. Two experts abstracted study characteristics and results independently for each article selected for inclusion. A third expert adjudicated disagreements. Separate meta-analyses were conducted to do the following: 1) examine the prevalence of each subtype/associated condition in concussion patients using a proportion, 2) assess subtype/associated conditions in concussion compared to baseline/uninjured controls using a prevalence ratio, and 3) compare the differences in symptom scores between concussion subtypes and uninjured/baseline controls using a standardized mean difference (SMD).

RESULTS

The most prevalent concussion subtypes for pediatric and adult populations were headache/migraine (0.52; 95% CI = 0.37, 0.67) and cognitive (0.40; 95% CI = 0.25, 0.55), respectively. In pediatric patients, the prevalence of the vestibular subtype was also high (0.50; 95% CI = 0.40, 0.60). Adult patients were 4.4, 2.9, and 1.7 times more likely to demonstrate cognitive, vestibular, and anxiety/mood subtypes, respectively, as compared with their controls (P < .05). Children and adults with concussion showed significantly more cognitive symptoms than their respective controls (SMD = 0.66 and 0.24; P < .001). Furthermore, ocular-motor in adult patients (SMD = 0.72; P < .001) and vestibular symptoms in both pediatric and adult patients (SMD = 0.18 and 0.36; P < .05) were significantly worse in concussion patients than in controls.

CONCLUSION

Five concussion subtypes with varying prevalence within 3 d following injury are commonly seen clinically and identifiable upon systematic literature review. Sleep disturbance, a concussion-associated condition, is also common. There was insufficient information available for analysis of cervical strain. A comprehensive acute concussion assessment defines and characterizes the injury and, therefore, should incorporate evaluations of all 5 subtypes and associated conditions.

Frequency of Primary Neck Pain in Mild Traumatic Brain Injury/Concussion Patients

OBJECTIVES

To determine (1) the frequency of neck pain overall and relative to other symptoms in patients presenting to a level I trauma center emergency department (ED) with mild traumatic brain injury (mTBI) and (2) the predictors of primary neck pain in this population.

DESIGN

Cohort study.

SETTING

Level I trauma center ED.

PARTICIPANTS

Patients presenting to the ED with symptoms of mTBI having been exposed to an event that could have caused mTBI (N=95).

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Frequency of self-reported neck pain as measured by Sport Concussion Assessment Tool 3 (SCAT3) symptom questionnaire at <3, 8, 15, and 45 days post injury. Primary neck pain was defined in 2 ways: (1) neck pain rated as equal or greater in severity than all other SCAT3 symptoms and (2) neck pain worse than all other symptoms.

RESULTS

The frequency of any reported neck pain was 68.4%, 50.6%, 49%, and 41.9% within 72 hours and at 8, 15, and 45 days, respectively. Frequency of primary neck pain (equal or worse/worse definitions) was 35.8%/17.9%, 34.9%/14.5%, 37%/14.8%, and 39.2%/10.8% across the 4 follow-up assessments. Participants who sustained their injuries in motor vehicle collisions had a higher rate of primary neck pain than those with other mechanisms of injury.

CONCLUSIONS

A sizable percentage of patients who present to level I trauma center EDs with mTBI report neck pain, which is commonly rated as similar to or worse than other mTBI-related symptoms. Primary neck pain is more common after motor vehicle collisions than with other mechanisms of injury. These findings support consensus statements identifying cervical injury as an important potential concurrent diagnosis in patients with mTBI.

Can the Neck Contribute to Persistent Symptoms Post Concussion? A Prospective Descriptive Case Series

BACKGROUND

Persistent symptoms post concussion can arise from a range of sources, including the neck. There is little description of neck assessment findings in people with persistent symptoms post concussion.

OBJECTIVES

To assess people with persistent symptoms following a concussion and determine whether the neck has also been injured, and to evaluate the potential of the neck to contribute to their symptoms.

METHODS

A consecutive series of participants (n = 20) referred for neck assessment were prospectively recruited by 2 providers of a multidisciplinary concussion service for people with persistent symptoms. Data were collected at initial assessment and on completion of neck treatment, which included standard questionnaires (Rivermead Post Concussion Symptoms Questionnaire, Neck Disability Index, Dizziness Handicap Inventory); patient-reported measures of headache, dizziness, and neck pain; physical examination findings; and details of comorbidities.

RESULTS

Participants were evaluated at a mean of 7.5 weeks post concussion (median, 5 weeks). On neck assessment, 90% were considered by the clinician to have a neck problem contributing to their current symptoms. Multiple findings were consistent with this view, including moderate-to-severe Neck Disability Index scores (mean ± SD, 33.4 ± 9.5 points), frequent neck pain (85%), frequent moderate-to-severe pain on occiput-C4 segmental assessment (85%), a positive flexion-rotation test (45%), and muscle tenderness (50%-55%).

CONCLUSION

Multiple findings were indicative of concurrent neck injury, particularly involving the upper cervical spine. These neck-related findings are important to recognize, as they have the potential to contribute to persistent symptoms post concussion and may respond to neck treatment. This study was prospectively registered with the Australian New Zealand Clinical Trials Registry (ACTRN12616001183471). J Orthop Sports Phys Ther 2019;49(11):845-854. Epub 1 Jun 2019. doi:10.2519/jospt.2019.8547.

Epidemiology of Cervical Muscle Strains in Collegiate and High School Football Athletes, 2011-2012 Through 2013-2014 Academic Years

CONTEXT

Cervical muscle strains are an often-overlooked injury, with neck- and spine-related research typically focusing on spinal cord and vertebral injuries.

OBJECTIVE

To examine the rates and distributions of cervical muscle strains in collegiate and high school football athletes.

DESIGN

Descriptive epidemiology study.

SETTING

Collegiate and high school football teams.

PATIENTS OR OTHER PARTICIPANTS

The National Collegiate Athletic Association Injury Surveillance Program (NCAA-ISP) collected data from collegiate football athletes. The High School National Athletic Treatment, Injury and Outcomes Network (HS NATION) and High School Reporting Information Online (HS RIO) collected data from high school football athletes. Data from the 2011-2012 through 2013-2014 academic years were used.

MAIN OUTCOME MEASURE(S)

Athletic trainers collected injury and exposure data for football players. Injury counts, injury rates per 10 000 athlete-exposures (AEs), and injury rate ratios with 95% confidence intervals (CIs) were calculated.

RESULTS

The NCAA-ISP reported 49 cervical muscle strains (rate = 0.96/10 000 AEs), of which 28 (57.1%) were TL (time loss; rate = 0.55/10 000 AEs). High School NATION reported 184 cervical muscle strains (rate = 1.66/10 000 AEs), of which 33 (17.9%) were TL injuries (rate = 0.30/10 000 AEs). The HS RIO, which collects only TL injuries, reported 120 TL cervical muscle strains (rate = 0.51/10 000 AEs). The overall injury rate was lower in the NCAA-ISP than in HS NATION (injury rate ratio = 0.58; 95% CI = 0.42, 0.79); when restricted to TL injuries, the overall injury rate was higher in the NCAA-ISP (injury rate ratio = 1.83; 95% CI = 1.11, 3.03). No differences were found when comparing TL injuries in HS RIO and the NCAA-ISP. Cervical muscle-strain rates were higher during competitions than during practices across all 3 surveillance systems for all injuries. Most cervical muscle strains were due to player contact (NCAA-ISP = 85.7%, HS NATION = 78.8%, HS RIO = 85.8%).

CONCLUSIONS

The incidence of cervical muscle strains in football players was low compared with other injuries. Nonetheless, identifying and implementing interventions, particularly those aimed at reducing unsafe player contact, are essential to further decrease the risk of injury and associated adverse outcomes.

Exploring the role of cervical spine endurance as a predictor of concussion risk and recovery following sports related concussion

BACKGROUND

Concussions have become a significant public health concern with rising incidence rates. Concussions have been shown to occur concurrently with neck injuries, such as whiplash-associated-disorder, therefore, understanding the role of the neck in concussions is important.

OBJECTIVES

To determine if there is a relationship between cervical muscle endurance and either concussion incidence, or concussion recovery in university athletes. Specifically, the primary aim was to investigate a relationship between pre-season deep neck flexor endurance test (DNFET) time in those who sustained an in-season injury versus those who did not. The secondary aim is to determine correlation in DNFET times and concussion recovery.

DESIGN

Longitudinal observational study.

METHODS

Pre-season DNFET was performed on university athletes. In the event of a concussion, cervical endurance and neuromuscular adaptation was re-assessed with the DNFET. Rehabilitative exercises were prescribed, as required, and DNFET was measured at subsequent treatments.

RESULTS

There was no significant difference between pre-season DNFET times and concussion incidence (p = 0.55). However, there was a moderate correlation between DNFET times and concussion recovery (R = 0.47, p = 0.001) whereby DNFET times improved predictively throughout rehabilitation.

CONCLUSIONS

While no statistically significant relationship was found between DNFET and concussion incidence, a significant clinical relationship was present with recovery. The validity of the DNFET test as a means for assessing risk or measuring recovery requires additional research.

EPIDEMIOLOGY of NECK INJURIES ACCOMPANYING SPORT CONCUSSIONS in YOUTH OVER a 13-YEAR PERIOD IN a COMMUNITY-BASED HEALTHCARE SYSTEM

Background

The same trauma that produces concussion may also produce neck injury. The signs of concussion and neck injury are similar, and symptoms after acceleration-deceleration trauma to the head-neck complex do not accurately discriminate between them. Research on the epidemiology of neck injury among sport-concussed youth is sparse.

Purpose

The purpose of this study was to investigate the epidemiology of diagnosed neck injury in non-sport-related concussion (Non-SRC) versus sport-related concussion (SRC) in youth by age, sex, and sport.

Study design

Cross-sectional epidemiologic study.

Methods

De-identified data from community-based electronic health records over 13 years were extracted to analyze rates and characteristics of neck injuries among non-SRCs and SRCs in youth aged five to 21. Neck injury diagnosis prevalence rates and odds ratios were calculated to estimate risk of neck injury among concussed youth, comparing non-SRCs to SRCs by age and sex.

Results

Sixteen thousand, eight hundred eighty-five concussion records were extracted, of which 3,040 SRCs and 2,775 non-SRCs in youth aged five to 21 were identified by cross-filtering sport-related keywords (e.g., football, basketball, soccer, running, swimming, batting, horseback riding, skiing, etc.) with all ICD-9 and ICD-10 concussion codes. The prevalence of neck injuries diagnosed among SRCs (7.2%) was significantly different than the prevalence of neck injuries diagnosed among non-SRCs (12.1%, p < 0.000). Neck injury diagnoses were significantly more prevalent in females overall (p < 0.000) and among non-SRCs (p < 0.000). The prevalence of neck injury diagnoses was not significantly higher in concussed females versus concussed males with SRC (p = 0.164).Among youth aged five to 21 exposed to concussions, non-SRCs were more likely to be accompanied by a neck injury diagnosis than SRCs (OR 1.66; 95% CI 1.39 to 1.98; p < 0.000). Similarly, female-to-male neck injury proportion ratios were significantly higher in females in non-SRCs compared to SRCs (IPR 1.90, 95% CI 1.60 to 2.25, p < 0.000).Sports with highest prevalence of concussion differ from sports with highest prevalence of concussion-related neck injury in both sexes.

Conclusions

The overall prevalence of diagnosed neck injuries in youth was higher in non-SRCs compared to SRCs (12.1 vs. 7.2%, p < 0.001), with the highest prevalence at age 14 in both sexes. The risk of neck injury diagnosis accompanying concussion was significantly higher in females compared to males (6.1% difference; p < 0.000).

How often is neck and vestibulo-ocular physiotherapy treatment recommended in people with persistent post-concussion symptoms? A retrospective analysis

BACKGROUND

Persistent post-concussion symptoms (PPCS) are complex, and typically involve multidisciplinary assessment and management. The neck and vestibulo-ocular systems are recognised as potential contributors to PPCS, yet it is not clear how often treatment for these systems is warranted.

OBJECTIVES

To explore how often neck and vestibulo-ocular treatment is received or recommended in people with PPCS.

DESIGN

Retrospective chart review.

METHOD

De-identified clinical service data for the calendar year of 2017 were extracted from a single concussion service provider in Dunedin, New Zealand. A summary of the individual assessments and treatments received were extracted and used to determine how often cases were considered to require physician or neuropsychological assessment; and how often cases received or were recommended neck and/or vestibulo-ocular physiotherapy treatment.

RESULTS/FINDINGS

147 cases were included in this study. Physician assessment was considered required in 25 cases (17%), and neuropsychological assessment in 90 cases (61%). For physiotherapy, neck treatment was received or recommended in 80 cases (54%), and vestibulo-ocular treatment in 106 cases (72%). Notably, this included 59 cases (40%) where both neck and vestibulo-ocular treatment were received or recommended.

CONCLUSIONS

The high proportion of cases receiving or recommended neck and vestibulo-ocular treatment strongly suggests both these systems often contribute to PPCS, often in overlap. While based on retrospective data, these findings highlight the value of routine neck and vestibulo-ocular examination in the assessment and management of PPCS. Further prospective study would be beneficial to explore these proportions in more detail and in other regions.

A Multidimensional Approach to Post-concussion Symptoms in Mild Traumatic Brain Injury

Mild traumatic brain injury (mTBI) presents a substantial burden to patients, families, and health care systems. Whereas, recovery can be expected in the majority of patients, a subset continues to report persisting somatic, cognitive, emotional, and/or behavioral problems, generally referred to as post-concussion syndrome (PCS). However, this term has been the subject of debate since the mechanisms underlying post-concussion symptoms and the role of pre- and post-injury-related factors are still poorly understood. We review current evidence and controversies concerning the use of the terms post-concussion symptoms vs. syndrome, its diagnosis, etiology, prevalence, assessment, and treatment in both adults and children. Prevalence rates of post-concussion symptoms vary between 11 and 82%, depending on diagnostic criteria, population and timing of assessment. Post-concussion symptoms are dependent on complex interactions between somatic, psychological, and social factors. Progress in understanding has been hampered by inconsistent classification and variable assessment procedures. There are substantial limitations in research to date, resulting in gaps in our understanding, leading to uncertainty regarding epidemiology, etiology, prognosis, and treatment. Future directions including the identification of potential mechanisms, new imaging techniques, comprehensive, multidisciplinary assessment and treatment options are discussed. Treatment of post-concussion symptoms is highly variable, and primarily directed at symptom relief, rather than at modifying the underlying pathology. Longitudinal studies applying standardized assessment strategies, diagnoses, and evidence-based interventions are required in adult and pediatric mTBI populations to optimize recovery and reduce the substantial socio-economic burden of post-concussion symptoms.

Prediction of Persistent Post-Concussion Symptoms after Mild Traumatic Brain Injury

Persistent post-concussion symptoms (PPCS) occur frequently after mild traumatic brain injury (mTBI). The identification of patients at risk for poor outcome remains challenging because valid prediction models are missing. The objectives of the current study were to assess the quality and clinical value of prediction models for PPCS and to develop a new model based on the synthesis of existing models and addition of complaints at the emergency department (ED). Patients with mTBI (Glasgow Coma Scale score 13-15) were recruited prospectively from three Dutch level I trauma centers between 2013 and 2015 in the UPFRONT study. PPCS were assessed using the Head Injury Severity Checklist at six months post-injury. Two prediction models (Stulemeijer 2008; Cnossen 2017) were examined for calibration and discrimination. The final model comprised variables of existing models with the addition of headache, nausea/vomiting, and neck pain at ED, using logistic regression and bootstrap validation. Overall, 591 patients (mean age 51years, 41% female) were included; PPCS developed in 241 (41%). Existing models performed poorly at external validation (area under the curve [AUC]: 0.57-0.64). The newly developed model included female sex (odds ratio [OR] 1.48, 95% confidence interval [CI] [1.01-2.18]), neck pain (OR 2.58, [1.39-4.78]), two-week post-concussion symptoms (OR 4.89, [3.19-7.49]) and two-week post-traumatic stress (OR 2.98, [1.88-4.73]) as significant predictors. Discrimination of this model was adequate (AUC after bootstrap validation: 0.75). Existing prediction models for PPCS perform poorly. A new model performs reasonably with predictive factors already discernible at ED warranting further external validation. Prediction research in mTBI should be improved by standardizing definitions and data collection and by using sound methodology.

Concussion and the autonomic nervous system: An introduction to the field and the results of a systematic review

BACKGROUND

Recent evidence suggests that autonomic nervous dysfunction may be one of many potential factors contributing to persisting post-concussion symptoms.

OBJECTIVE

This is the first systematic review to explore the impact of concussion on multiple aspects of autonomic nervous system functioning.

METHODS

The methods employed are in compliance with the American Academy of Neurology (AAN) and PRISMA standards. Embase, MEDLINE, PsychINFO, and Science Citation Index literature searches were performed using relevant indexing terms for articles published prior to the end of December 2016. Data extraction was performed by two independent groups, including study quality indicators to determine potential risk for bias according to the 4-tiered classification scheme of the AAN.

RESULTS

Thirty-six articles qualified for inclusion in the analysis. Only three studies (one Class II and two Class IV) did not identify anomalies in measures of ANS functioning in concussed populations.

CONCLUSIONS

The evidence supports the conclusion that it is likely that concussion causes autonomic nervous system anomalies. An awareness of this relationship increases our understanding of the physical impact of concussion, partially explains the overlap of concussion symptoms with other medical conditions, presents opportunities for further research, and has the potential to powerfully inform treatment decisions.

Understanding the complete pathophysiology of chronic mild to moderate neck pain: Implications for the inclusion of a comprehensive sensorimotor evaluation

BACKGROUND

Inconsistencies in the literature concerning the effect of neck pain have led to a lack of understanding concerning the complete pathophysiology of neck pain. While the effect of neck pain on motor function as measured by active range of motion and isometric neck strength is well documented the effect of neck pain on sensory measures such as tactical acuity and neck reposition error (NRE) remain poorly understood.

OBJECTIVE

The purpose of this study was to evaluate a combined sensorimotor evaluation to explore the potential benefits of incorporating both sensory and motor task into a physical evaluation of neck pain suffers to gain an added knowledge of the complete pathophysiology of their health status.

METHODS

A cross-sectional study that measured neck joint reposition error, tactical acuity, neck isometric strength and range of motion in 40 volunteer participants (22 pain, 18 control).

RESULTS

A statistically significant increase in NRE in flexion (2.75∘± 1.52∘ vs. 4.53∘± 1.74∘ and in extension (3.78∘± 1.95∘ vs 5.77∘± 2.73∘ in participants suffering from neck pain was observed. Additionally, the dermatome C5 was found to be the most affected. No differences were found in neck strength or neck range of motion between healthy controls and patients with chronic moderate neck pain.

COACH CV: The Seven Clinical Phenotypes of Concussion

Our understanding of the diverse physiological manifestations of concussion is changing rapidly. This has an influence on the clinical assessment of patients who have sustained a concussion. The 2017 Consensus Statement on Concussion in Sport states that numerous post-injury clinical findings, such as cognitive deficits, post-traumatic headaches, dizziness, difficulties with oculomotor function, and depression have all been associated with a poorer prognosis in concussed patients. This demonstrates that there are several potential clinical manifestations after head injury warranting clinical evaluation. We have developed an acronym to guide the office-based assessment of concussed patients to consider each of the potential clinical phenotypes. "COACH CV" prompts the clinician to evaluate for cognitive problems, oculomotor dysfunction, affective disturbances, cervical spine disorders, headaches, and cardiovascular and vestibular anomalies.

Moving concussion care to the next level: The emergence and role of concussion clinics in the UK

Concussion is a worldwide issue in sports medicine at present, and in recent years has evolved into a major consideration for sports in the United Kingdom (UK). Governing bodies, sports clinicians, and indeed athletes themselves are dealing with the implications that this injury brings. In parallel with this, innovative means of managing this condition are emerging. The creation of specialized concussion clinics (which mirror those present in the United States and Canada) is one means of enhancing concussion care in the UK. In this chapter, the emergence of concussion clinics in the UK will be discussed. The specific roles of the multidisciplinary teams working in these clinics will be outlined (including the disciplines of sports medicine, radiology, neurology, physiotherapy, and psychology/psychiatry), and the approaches used in the management of concussion in this setting will be explored. Future recommendations for the growth and development of clinic-based concussion care in the UK will also be discussed.

Dizziness, Unsteadiness, Visual Disturbances, and Sensorimotor Control in Traumatic Neck Pain

Synopsis There is considerable evidence to support the importance of cervical afferent dysfunction in the development of dizziness, unsteadiness, visual disturbances, altered balance, and altered eye and head movement control following neck trauma, especially in those with persistent symptoms. However, there are other possible causes for these symptoms, and secondary adaptive changes should also be considered in differential diagnosis. Understanding the nature of these symptoms and differential diagnosis of their potential origin is important for rehabilitation. In addition to symptoms, the evaluation of potential impairments (altered cervical joint position and movement sense, static and dynamic balance, and ocular mobility and coordination) should become an essential part of the routine assessment of those with traumatic neck pain, including those with concomitant injuries such as concussion and vestibular or visual pathology or deficits. Once adequately assessed, appropriate tailored management should be implemented. Research to further assist differential diagnosis and to understand the most important contributing factors associated with abnormal cervical afferent input and subsequent disturbances to the sensorimotor control system, as well as the most efficacious management of such symptoms and impairments, is important for the future. J Orthop Sports Phys Ther 2017;47(7):492-502. Epub 16 Jun 2017. doi:10.2519/jospt.2017.7052.

Clinical characteristics and outcomes of treatment of the cervical spine in patients with persistent post-concussion symptoms: A retrospective analysis

BACKGROUND

Concussion is typically defined as a mild brain injury, and yet the brain is unlikely to be the only source of persistent post-concussion symptoms. Concurrent injury to the cervical spine in particular is acknowledged as a potential source of common persistent symptoms such as headache, dizziness and neck pain.

OBJECTIVES

To describe the cervical spine findings and outcomes of treatment in a series of patients with persistent post-concussion symptoms, and describe the clinical characteristics of a cervicogenic component when it is present.

DESIGN

Retrospective chart review of a consecutive series of patients with concussion referred to a physiotherapist for cervical spine assessment.

METHOD

Patient charts for all patients over a calendar year referred by a concussion service provider to a physiotherapist for cervical spine assessment were de-identified and transferred to the research team. Clinical data were independently extracted by two research assistants and analysed using descriptive statistics.

RESULTS/FINDINGS

Data were analysed from 46 patient charts. Those with a cervicogenic component (n = 32) were distinguished from those without a cervicogenic component (n = 14) by physical examination findings, particularly pain on manual segmental examination. Physiotherapy treatment of the cervicogenic component (n = 21) achieved improvements in function (mean increase of 3.8 in the patient-specific functional scale), and pain (mean decrease of 4.6 in the numeric pain-rating scale).

CONCLUSIONS

The clinical characteristics described give preliminary support to the idea that the cervical spine may contribute to persistent post-concussion symptoms, and highlight the value of physiotherapy assessment and treatment of the cervical spine following a concussive injury.

Return to School and Learning After Concussion: Tips for Pediatricians

Concussion in children and adolescents is a common injury that is usually managed by the primary care provider. Students with a concussion may present with a variety of symptoms, and these symptoms interfere with regular school participation. Optimizing the timing and progression of return to school and learning is often challenging, but with a careful history and concussion-specific examination, the primary care provider can identify potential barriers to school reentry. This review focuses on developing a systematic approach to the initial concussion evaluation and developing customized school accommodations to aid in the school reentry process. [Pediatr Ann. 2017;46(3):e93-e98.].

Cervical Injury Assessments for Concussion Evaluation: A Review

BACKGROUND

A concussion is a complex pathophysiologic process that is induced by biomechanical forces and affects the brain. Cervical injuries and concussion can share similar mechanisms and nearly identical symptoms or causes. Therefore, symptoms or causes alone may be insufficient to differentiate between patients with a concussion and patients with cervical injuries.

OBJECTIVE

To demonstrate the homogeneous causes and symptoms observed in patients with a concussion and patients with cervical injury and to provide information on clinical tests that can differentiate cervical injury from pathologic conditions of vestibular or central origin.

SUMMARY

Given that concussion and cervical injury share similar causes and symptoms, this information alone may be insufficient to diagnose a concussion. Clinical assessments, such as the cervical joint-reposition error test, smooth-pursuit neck-torsion test, head-neck differentiation test, cervical flexion-rotation test, and physical examination of the cervical spine, can be performed after a head and neck pathomechanical event to identify the presence of cervical injury. Differentiating between a concussion and cervical injury is clinically vital for timely and appropriate evidence-based treatment.

CONCLUSIONS

Specific clinical tests should be used after a head and neck pathomechanical event to differentiate between symptoms due to a concussion and cervical injury. Continued research on the clinical utility of the 5 identified cervicogenic tests is also recommended.

Whiplash Injury or Concussion? A Possible Biomechanical Explanation for Concussion Symptoms in Some Individuals Following a Rear-End Collision

Study Design Finite element modeling of experimental data. Background The clinical presentations of whiplash injury and concussion have considerable overlap. Both diagnoses are generally based on presenting signs and symptoms, and a history of neck or head trauma. With incomplete knowledge of the trauma, differentiating between whiplash injury and concussion can be clinically challenging. Objectives To estimate the brain strains that develop during rear-end car crashes, evaluate how these strains vary with different head kinematic parameters, and compare these strains to those generated during potentially concussive football helmet impacts. Methods Head kinematic data were analyzed from 2 prior studies, one that focused on head restraint impacts in rear-end crash tests and another that focused on football helmet impacts. These data were used as inputs to a finite element model of the human brain. Brain strains were calculated and compared to different peak kinematic parameters and between the 2 impact conditions. Results Brain strains correlated best with the head's angular velocity change for both impact conditions. The 4 crashes with head angular velocity changes greater than 30 rad/s (greater than 1719°/s) generated the highest brain stains. One crash, in which the head wrapped onto the top of the head restraint, generated brain strains similar to a 9.3-m/s rear football helmet impact, a level previously associated with concussion. Conclusion This work provides new insight into a potential biomechanical link between whiplash injury and concussion, and advances our understanding of how head restraint interaction during a rear-end crash may cause an injury more typically associated with sports-related head impacts. J Orthop Sports Phys Ther 2016;46(10):874-885. doi:10.2519/jospt.2016.7049.

Chiropractic Management of Musculoskeletal Symptoms in a 14-Year-Old Hockey Player With Postconcussion Symptoms: A Case Report

OBJECTIVE

The purpose of this study is to describe the chiropractic management of a student athlete with postconcussion syndrome.

CLINICAL FEATURES

A 14-year-old male hockey player presented to a chiropractic clinic with postconcussion symptoms 13 days after his initial injury. He experienced an occipital headache with a pain rating of 8/10, upset stomach, blurry vision, nausea, dizziness, balance problems, a "foggy feeling," difficulty with concentration, difficulty with memory, fatigue, confusion, drowsiness, and irritability. Prior to seeing the doctor of chiropractic, the patient was monitored by a medical doctor, and the care he had been receiving was in accordance with current concussion guidelines. At the time of presentation to the chiropractic clinic, he had failed to progress toward return to play, and his computerized neurocognitive testing scores had not improved.

INTERVENTION AND OUTCOME

Chiropractic manipulative therapy, myofascial release, instrument-assisted soft tissue technique, and therapeutic exercises were provided over 5 treatments spanning a 20-day period. The patient followed up each treatment with ImPACT testing. At the conclusion of the treatments, the patient's computerized neurocognitive testing scores had improved, and the patient was returned to play.

CONCLUSION

This case demonstrates the improvement of postconcussion syndrome in a 14-year-old male hockey player under chiropractic management.