Objectives: To assess injury rates in all mixed martial arts (MMA) studies.
Methods: Six online databases were searched until November 2017 including MEDLINE, EMBASE, CINAHL, Web of Science, PubMed, Google/Google Scholar and conference proceedings. All included studies were entered in Pub Med Single Citation Matcher and all citation chains followed. Abstracts and titles were assessed for relevance, data independently abstracted and risk of bias for all competition studies evaluated independently by two reviewers.
Results: There are data for 5,374 male and 108 female MMA fighters. For 2407 males the weighted average injury rate/1000Athletic Encounters (AE) was 246.4 and for one study of 108 females 101.9. One study provided data by professional status: professionals 135.5/1000AE and amateurs 71.0/1000AE. Reasons for stopping matches were knockout/technical knockout 173.9/1000AE for males and 175.9/1000AE for females, submission 228.6/1000AE, and referee's decision 98.2/1000AE. Losers can experience large amounts of trauma especially head trauma as matches terminate. Two studies of competitions provided personally conducted ringside assessments and both pre- and post-match examination results. The other studies reported retrospective assessments of fight records or videos or videos and scorecards. There are no studies of training injuries of professionals or injuries of amateurs or long-term follow-up of musculoskeletal injuries or neurological damage. Studies are limited to the US and Canada. There are no systematic reviews of newspaper or media accounts of fights to assess rates and numbers of injuries or mortality. The few published surveys and case reports markedly understate the worldwide situation.
Conclusions: There are high rates of trauma in MMA. The authorities who regulate MMA and referees and physicians who monitor MMA fighters have an inadequate database to guide their work. Researchers need to adopt the same set of complete definitions of all possible injuries and measure the high and early rate of neurological damage.
Keywords: Mixed martial arts; systematic review; wounds and injuries.