Video analysis of acute motor and convulsive manifestations in sport-related concussion.
ABSTRACT To describe the motor and convulsive manifestations in acute sports-related head injury.
A total of 234 cases of concussive injuries during the 1995 through 1997 football seasons were obtained from the Australian Football League Medical Officers Association injury survey. Of these, 102 cases were recorded adequately on television videotape and were analyzed by two independent observers using a standardized recording form detailing injury mechanics and clinical features of the episodes. Motor and convulsive features were correlated with mechanical variables and with duration of loss of consciousness using linear modeling techniques.
Tonic posturing occurred in 25 subjects, clonic movements in 6, righting movement in 40, and gait unsteadiness in 42. In one subject the tonic and clonic features were sufficiently prolonged to be deemed a concussive convulsion. The only risk factor for tonic posturing using logistic regression was the presence of loss of consciousness (p = 0.0001). There was a trend toward facial impact being an independent predictor of tonic posturing but this did not reach significance. No other independent variable predicted the development of clonic movements, righting movements, or gait unsteadiness.
Subtle motor manifestations such as tonic posturing and clonic movements commonly occur in concussion; the main predictive factor for tonic posturing is the presence of loss of consciousness. The authors speculate that these clinical features are due to brainstem dysfunction secondary to biomechanical forces inducing a transient functional decerebration.
[Show abstract] [Hide abstract]
ABSTRACT: Head injury in children is one of the most common causes of death and disability in the US and, increasingly, worldwide. This chapter reviews the causes, patterns, pathophysiology, and treatment of head injury in children across the age spectrum, and compares pediatric head injury to that in adults. Classification of head injury in children can be organized according to severity, pathoanatomic type, or mechanism. Response to injury and repair mechanisms appear to vary at different ages, and these may influence optimal treatment; however, much work is still needed before investigation leads to clearly effective clinical interventions. This is true both for the more severe injuries as well as those at the milder end of the injury spectrum, the latter of which have received increasing attention. In this chapter, neuroassessment tools for each age, newer imaging modalities including magnetic resonance imaging (MRI), and specific pediatric management issues, including intracranial pressure (ICP) monitoring and seizure prophylaxis, are reviewed. Finally, specific head injury patterns and functional outcomes relevant to pediatric patients are discussed. While head injury is common, the number of head-injured children is significantly smaller than the corresponding adult head-injured population. When divided further by specific ages, injury types, and other sources of heterogeneity, properly powered clinical research is likely to require large data sets that will allow for stratification across variables, including age. While much has been learned in the past several decades, further study will be required to determine the best management practices for optimizing recovery in individual pediatric patients. This approach is likely to depend on collaborative international head injury databases that will allow researchers to better understand the nuanced evolution of different types of head injury in patients at each age, and the pathophysiologic, treatment-related, and genetic factors that influence recovery. © 2015 Elsevier B.V. All rights reserved.Handbook of Clinical Neurology 01/2015; 127:219-42. DOI:10.1016/B978-0-444-52892-6.00015-5
[Show abstract] [Hide abstract]
ABSTRACT: Long-term neurological damage as a result of head trauma while playing sports is a major concern for football athletes today. Repetitive concussions have been linked to many neurological disorders. Recently, it has been reported that repetitive sub-concussive events can be a significant source of accrued damage. Since football athletes can experience hundreds of sub-concussive hits during a single season, it is of utmost importance to understand their effect on brain health in the short- and long-term. In this study, resting state functional magnetic resonance imaging (rs-fMRI) was used to study changes in the Default Mode Network (DMN) after repetitive sub-concussive mTBI. Twenty-two high school American football athletes, clinically asymptomatic, were scanned using rs-fMRI for a single season. Baseline scans were acquired before the start of the season, and follow-up scans were obtained during and after the season to track the potential changes in the DMN as a result of experienced trauma. Ten non-collision-sport athletes were scanned over two sessions as controls. Overall, football athletes had significantly different functional connectivity measures than controls for most of the year. The presence of this deviation of football athletes from their healthy peers even before the start of the season suggests a neurological change that has accumulated over the years of playing the sport. Football athletes also demonstrate short-term changes relative to their own baseline at start of the season. Football athletes exhibited hyper-connectivity in the DMN compared to controls for most of the sessions, which indicates that, despite the absence of symptoms typically associated with concussion, the repetitive trauma accrued produced long-term brain changes compared to their healthy peers.09/2014; 5(2). DOI:10.1089/brain.2014.0279
[Show abstract] [Hide abstract]
ABSTRACT: Interrater agreement evaluation of a tool to document and code the situational factors and mechanisms of knockouts (KOs) and technical knockouts (TKOs) in mixed martial arts (MMA). Retrospective case series. Professional MMA matches from the Ultimate Fighting Championship-2006-2012. Two nonmedically trained independent raters. The MMA Knockout Tool (MMA-KT) consists of 20 factors and captures and codes information on match characteristics, situational context preceding KOs and TKOs, as well as describing competitor states during these outcomes. The MMA-KT also evaluates the mechanism of action and subsequent events surrounding a KO. The 2 raters coded 125 unique events for a total of 250 events. The 8 factors of Part A had an average κ of 0.87 (SD = 0.10; range = 0.65-0.98); 7 were considered "substantial" agreement and 1 "moderate." Part B consists of 12 factors with an average κ of 0.84 (SD = 0.16; range = 0.59-1.0); 7 classified as "substantial" agreement, 4 "moderate," and 1 "fair." The majority of the factors in the MMA-KT demonstrated substantial interrater agreement, with an average κ of 0.86 (SD = 0.13; range = 0.59-1.0). The MMA-KT is a reliable tool to extract and code relevant information to investigate the situational factors and mechanism of KOs and TKOs in MMA competitions.Clinical journal of sport medicine: official journal of the Canadian Academy of Sport Medicine 12/2013; DOI:10.1097/JSM.0000000000000047 · 2.01 Impact Factor