Traumatic brain injuries in mixed martial arts: A systematic review

Abstract

Introduction: Mixed martial arts is an emerging combat sport that is gaining popularity worldwide. We systematically reviewed the literature regarding the prevalence, severity and risk factors of head injuries sustained in mixed martial arts activities. Methods: We conducted a comprehensive systematic review of Ovid MEDLINE, Embase, PsycINFO, EBM Reviews, CINAHL, SPORTDiscus, and Web of Science from 1990 to 2016 for studies of any design that reported associations of acute or chronic head injuries in persons participating in mixed martial arts activities. Results: The initial database search yielded a total 472 citations, including 264 unique citations after duplications were removed. A total of 18 articles, primarily of observational data, showed ‘technical knockouts’ and ‘knockouts’ are prevalent in this sport (range: 28.3–46.2% of all matches) with other studies showing the lifetime average of 6.2 technical knockouts or knockouts in a career. Studies used inconsistent reporting methods for concussion, and no information regarding long-term follow-up was available. Conclusion: Mixed martial arts fighting may be associated with repetitive head injuries and potential long-term neurological consequences; however, data on this topic are poor. Larger studies and stringent medical oversight are needed to improve the management and understanding of mixed martial arts head injuries, with implementation of harm reduction strategies and/or rule modifications to prevent long-term neurological sequelae. Systematic Review Registration: PROSPERO – CRD42014010019.