RT Journal Article
SR Electronic
T1 What is the physiological time to recovery after concussion? A systematic review
JF British Journal of Sports Medicine
JO Br J Sports Med
FD BMJ Publishing Group Ltd and British Association of Sport and Exercise Medicine
SP 935
OP 940
DO 10.1136/bjsports-2016-097464
VO 51
IS 12
A1 Kamins, Joshua
A1 Bigler, Erin
A1 Covassin, Tracey
A1 Henry, Luke
A1 Kemp, Simon
A1 Leddy, John J
A1 Mayer, Andrew
A1 McCrea, Michael
A1 Prins, Mayumi
A1 Schneider, Kathryn J
A1 Valovich McLeod, Tamara C
A1 Zemek, Roger
A1 Giza, Christopher C
YR 2017
UL http://bjsm.bmj.com/content/51/12/935.abstract
AB Aim or objective The aim of this study is to consolidate studies of physiological measures following sport-related concussion (SRC) to determine if a time course of postinjury altered neurobiology can be outlined. This biological time course was considered with respect to clinically relevant outcomes such as vulnerability to repeat injury and safe timing of return to physical contact risk.Design Systematic review.Data sources PubMed, CINAHL, Cochrane Central, PsychINFO.Eligibility criteria for selecting studies Studies were included if they reported original research on physiological or neurobiological changes after SRC. Excluded were cases series <5 subjects, reviews, meta-analyses, editorials, animal research and research not pertaining to SRC.Results A total of 5834 articles were identified, of which 80 were included for full-text data extraction and review. Relatively few longitudinal studies exist that follow both physiological dysfunction and clinical measures to recovery.Summary/conclusions Modalities of measuring physiological change after SRC were categorised into the following: functional MRI, diffusion tensor imaging, magnetic resonance spectroscopy, cerebral blood flow, electrophysiology, heart rate, exercise, fluid biomarkers and transcranial magnetic stimulation. Due to differences in modalities, time course, study design and outcomes, it is not possible to define a single ‘physiological time window’ for SRC recovery. Multiple studies suggest physiological dysfunction may outlast current clinical measures of recovery, supporting a buffer zone of gradually increasing activity before full contact risk. Future studies need to use generalisable populations, longitudinal designs following to physiological and clinical recovery and careful correlation of neurobiological modalities with clinical measures.