Concussion with transient loss of consciousness (tLOC) is a commonly observed but poorly understood phenomenon with mounting clinical significance. This study aimed to examine the relationship between head motion in varying planes and tLOC in athletes with brain injuries.
A case-control design was utilized. The Ultimate Fighting Championship database was screened for events ending with knockouts (KO) from 2013 to 2016. Time of strike, striking implement, strike location, and head motion were recorded for all KO strikes (cases), and for a subset of non-KO strikes (controls). Characteristics of winners and losers were compared using 2-tailed t-tests. Multivariate logistic regression was used to determine odds ratios for strike characteristics associated with tLOC. The Kaplan-Meier estimate was used to describe the temporal distribution of KO’s.
136 fights were identified and 110 videos were included. Head motion in the axial plane was strongly associated with tLOC (OR, 45.3; 95% CI, 20.8 - 98.6). Other predictors of tLOC were head motion in sagittal and coronal planes, non-fist striking implements and strikes to the mandible or maxilla. The Kaplan-Meier survival curve demonstrated a decreasing rate of KO’s through time.
Rotational head acceleration, particularly in the axial plane, is strongly associated with tLOC.
1Department of Neurology, Division of Physical Medicine & Rehabilitation, Washington University School of Medicine, St Louis, MO, USA
2Department of Anesthesiology, Washington University School of Medicine, St Louis, MO, USA
3Department of Epidemiology, Biostatistics and Occupational Health, McGill University, Montreal, Canada
4Departments of Orthopedic Surgery and Neurology, Division of Physical Medicine & Rehabilitation, Washington University School of Medicine, St Louis, MO, USA
5Segal and Lyer Orthodontics, New Jersey, USA
6Department of Neurology, Uniformed Services University of the Health Sciences, Bethesda, MD; Department of Neurology, The Johns Hopkins University School of Medicine, Baltimore, MD
7Department of Neurology, Uniformed Services University of the Health Sciences, Bethesda, MD; Behavioral Biology Branch, Walter Reed Army Institute of Research, Silver Spring, MD
CORRESPONDENCES: Alexandra Fogarty, Washington University, PM&R Division, 4444 Forest Park Avenue, St Louis, MO. Tel: (314) 319-9807, firstname.lastname@example.org
DISCLOSURES: The authors have no competing interests. No funding, grants or equipment was provided for the project from any source. There were no financial benefits to the authors. The manuscript has not been previously presented or published.