Objective: There has been considerable attention brought to the detection and evaluation of concussive injuries across many different sports. The Kind-Devick (K-D) test has been utilized as a tool to screen for concussive injury in multiple sports including boxing, mixed martial arts (MMA), hockey, amateur rugby, and high school football. The aim of this study was to determine the effect of training or a brain “event” such as knock-outs (KO), chokes, near chokes, concussions or tap outs on brain function as assessed by the K-D test in adult mixed martial arts athletes.
Methods: Adult MMA athletes (n = 54, mean age 29.9 ± 6.9) underwent baseline K-D testing prior to and following a workout or sanctioned fight. Pre workout and pre fight K-D testing was administered prior to practice in the workout group and on the weigh-in day prior to a scheduled fight. Post-practice and post-fight K-D testing was administered immediately following practice or within 10 minutes of fight completion.
Results: K-D tests worsened (longer duration) in athletes that had an “event” (N = 13) (44.8 ± 7.0 s vs 49.5 ± 8.2, median change -6.0 seconds, p = 0.0210, Wilcoxon signed rank test). K-D tests improved (shorter duration) following a standard workout or following a fight in which no “event” occurred (n = 48) (51.1 ± 11.7 s vs 44.5 ± 6.9 s, median change 4.73 seconds, p = <0.0001, Wilcoxon signed-rank).
Conclusion: Slowing (worsening) of the post-fight K-D test is a reliable method for identifying MMA fighters with significant injury due to a choke, near choke, KO, tap out or concussion. These injuries mimic concussive injury K-D test scores from other contact sports.
Summary Points:
- K-D Test performance worsened in athletes with an event (choke, near choke, knock out, tap out or concussion).
- K-D Test performance improved after workout in the absence of any event.
- Slowing of post-fight K-D Test is a reliable method for identifying MMA fighters with significant injury due to choke, near choke, KO, tap out or concussion.