Cerebral Blood Flow During Treadmill Exercise Is a Marker of Physiological Postconcussion Syndrome in Female Athletes

Sport-related concussion induces transient cardiovascular autonomic dysfunction

Recent evidence suggests that concussions may disrupt autonomic cardiovascular control. This study investigated the initial effects of concussion on cardiovascular function using three autonomic reflex tests. Twenty-three recreational athletes (12 women, 11 men) were divided into concussed ( n = 12) and control ( n = 11) groups. Concussed participants performed forced breathing, standing, and Valsalva autonomic tests four times: 1) within 48 h of injury; 2) 24 h later; 3) 1 wk after injury; and 4) 2 wk after injury. The controls performed the same tests on the same schedule. Differences in heart rate (HR), systolic blood pressure (SBP), and diastolic blood pressure (DBP) responses to the tests were continuously measured using finger photoplethysmography and were analyzed using repeated-measures multivariate ANOVAs and ANOVAs. Within 48 h of injury, the concussed group had significantly greater resting SBP ( t21= 2.44, P = 0.02, d = 1.03), HR ( t21= 2.33, P = 0.03, d = 1.01), and SBP responses to standing ( t21= 2.98, P = 0.01, d = 1.24), and 90% SBP normalization times ( t21= 2.64, P = 0.02, d = 1.10) after the Valsalva, but those group differences subsided 24 h later. There was also a significant interaction with the HR responses to forced breathing ( F3,60= 4.13, P = 0.01, ηp2= 0.17), indicating the concussed responses declined relative to the control’s over time. The results demonstrate that concussion disrupted autonomic cardiovascular control, and that autonomic reflex tests are practical means by which to evaluate that dysfunction.

Rest and treatment/rehabilitation following sport-related concussion: a systematic review

AIM OR OBJECTIVE

The objective of this systematic review was to evaluate the evidence regarding rest and active treatment/rehabilitation following sport-related concussion (SRC).

DESIGN

Systematic review.

DATA SOURCES

MEDLINE (OVID), CINAHL (EbscoHost), PsycInfo (OVID), Cochrane Central Register of Controlled Trials (OVID), SPORTDiscus (EbscoHost), EMBASE (OVID) and Proquest DissertationsandTheses Global (Proquest) were searched systematically.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Studies were included if they met the following criteria: (1) original research; (2) reported SRC as the diagnosis; and (3) evaluated the effect of rest or active treatment/rehabilitation. Review articles were excluded.

RESULTS

Twenty-eight studies met the inclusion criteria (9 regarding the effects of rest and 19 evaluating active treatment). The methodological quality of the literature was limited; only five randomised controlled trials (RCTs) met the eligibility criteria. Those RCTs included rest, cervical and vestibular rehabilitation, subsymptom threshold aerobic exercise and multifaceted collaborative care.

SUMMARY/CONCLUSIONS

A brief period (24-48 hours) of cognitive and physical rest is appropriate for most patients. Following this, patients should be encouraged to gradually increase activity. The exact amount and duration of rest are not yet well defined and require further investigation. The data support interventions including cervical and vestibular rehabilitation and multifaceted collaborative care. Closely monitored subsymptom threshold, submaximal exercise may be of benefit.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO 2016:CRD42016039570.

Uncoupling between cerebral perfusion and oxygenation during incremental exercise in an athlete with postconcussion syndrome: a case report

High-intensity exercise may pose a risk to patients with postconcussion syndrome (PCS) when symptomatic during exertion. The case of a paralympic athlete with PCS who experienced a succession of convulsion-awakening periods and reported a marked increase in postconcussion symptoms after undergoing a graded symptom-limited aerobic exercise protocol is presented. Potential mechanisms of cerebrovascular function failure are then discussed.

Efficiency of an Active Rehabilitation Intervention in a Slow-to-Recover Paediatric Population following Mild Traumatic Brain Injury: A Pilot Study

Objective. The aim of this study was to identify whether the addition of an individualised Active Rehabilitation Intervention to standard care influences recovery of young patients who are slow-to-recover following a mTBI. Methods. Fifteen participants aged 15 ± 2 years received standard care and an individualised Active Rehabilitation Intervention which included (1) low- to high-intensity aerobic training; (2) sport-specific coordination exercises; and (3) therapeutic balance exercises. The following criteria were used to measure the resolution of signs and symptoms of mTBI: (1) absence of postconcussion symptoms for more than 7 consecutive days; (2) cognitive function corresponding to normative data; and (3) absence of deficits in coordination and balance. Results. The Active Rehabilitation Intervention lasted 49 ± 17 days. The duration of the intervention was correlated with self-reported participation ([Formula: see text]%, r = -0.792, p < 0.001). The average postconcussion symptom inventory (PCSI) score went from a total of 36.85 ± 23.21 points to 4.31 ± 5.04 points after the intervention (Z = -3.18, p = 0.001). Conclusion. A progressive submaximal Active Rehabilitation Intervention may represent an important asset in the recovery of young patients who are slow-to-recover following a mTBI.

Graded aerobic treadmill testing in pediatric sports-related concussion: safety, clinical use, and patient outcomes

OBJECTIVE The objectives of this study were 2-fold: 1) to evaluate the safety, tolerability, and clinical use of graded aerobic treadmill testing in pediatric patients with sports-related concussion (SRC), and 2) to evaluate the clinical outcomes of treatment with a submaximal aerobic exercise program in patients with physiological post-concussion disorder (PCD). METHODS The authors conducted a retrospective chart review of pediatric patients (age < 20 years) with SRC who were referred to a multidisciplinary pediatric concussion program and underwent graded aerobic treadmill testing between October 9, 2014, and February 11, 2016. Clinical assessments were carried out by a single neurosurgeon and included clinical history taking, physical examination, and recording specific patient-reported concussion-related symptoms using the Post-Concussion Symptom Scale (PCSS). Graded aerobic treadmill testing using a modified Balke protocol for incremental increases in intensity was used as a diagnostic tool to assess physiological recovery, classify post-concussion syndrome (PCS) subtype, and reassess patients following treatment. Patients with a symptom-limited threshold on treadmill testing (physiological PCD) were treated with an individually tailored submaximal exercise prescription and multidisciplinary targeted therapies. RESULTS One hundred six patients (mean age 15.1 years, range 11-19 years) with SRC underwent a total of 141 treadmill tests. There were no serious complications related to treadmill testing in this study. Overall, 138 (97.9%) of 141 tests were well tolerated and contributed valuable clinical information. Treadmill testing confirmed physiological recovery in 63 (96.9%) of 65 patients tested, allowing successful return to play in 61 (93.8%). Treadmill testing was used to diagnose physiological PCD in 58 patients and cervicogenic PCD in 1 patient. Of the 41 patients with physiological PCD who had complete follow-up and were treated with tailored submaximal exercise prescription, 37 (90.2%) were classified as clinically improved and 33 (80.5%) successfully returned to sporting activities. Patients who did not respond or experienced an incomplete response to submaximal aerobic exercise treatment included 7 patients with migraine headaches and 1 patient with a postinjury psychiatric disorder. CONCLUSIONS Graded aerobic treadmill testing is a safe, tolerable, and clinically valuable tool that can assist in the evaluation and management of pediatric SRC. Future research is needed to confirm the clinical value of this tool in return-to-play decision making. Studies are also needed to understand the pathophysiology of physiological PCD and the effects of targeted treatment.

Multi-Disciplinary Management of Athletes with Post-Concussion Syndrome: An Evolving Pathophysiological Approach

Historically, patients with sports-related concussion (SRC) have been managed in a uniform fashion consisting mostly of prescribed physical and cognitive rest with the expectation that all symptoms will spontaneously resolve with time. Although this approach will result in successful return to school and sports activities in the majority of athletes, an important proportion will develop persistent concussion symptoms characteristic of post-concussion syndrome (PCS). Recent advances in exercise science, neuroimaging, and clinical research suggest that the clinical manifestations of PCS are mediated by unique pathophysiological processes that can be identified by features of the clinical history and physical examination as well as the use of graded aerobic treadmill testing. Athletes who develop PCS represent a unique population whose care must be individualized and must incorporate a rehabilitative strategy that promotes enhanced recovery of concussion-related symptoms while preventing physical deconditioning. In this review, we present our evolving evidence-based approach to evaluation and management of athletes with PCS that aims to identify the pathophysiological mechanisms mediating persistent concussion symptoms and guides the initiation of individually tailored rehabilitation programs that target these processes. In addition, we outline the important qualified roles that multi-disciplinary healthcare professionals can play in the management of this patient population, and discuss where future research efforts must be focused to further evaluate this evolving pathophysiological approach.