Dangers of Mixed Martial Arts in the Development of Chronic Traumatic Encephalopathy

Impact of repeated sportive chokes on carotid intima media thickness and brain injury biomarkers in grappling athletes

PURPOSE

Vascular neck compression techniques, referred to as 'chokes' in combat sports, reduce cerebral perfusion, causing loss of consciousness or voluntary submission by the choked athlete. Despite these chokes happening millions of times yearly around the world, there is scant research on their long-term effects. This pilot study evaluated whether repeated choking in submission grappling impacts the carotid intima media thickness (CIMT) and brain injury biomarkers (NFL, hGFAP, t-Tau, and UCH-L1).

METHODS

Participants (n = 39, 29 male; ages 27-60 years) were assigned to one of two study arms: Grapplers (n = 20, 15 male) and 19 age/sex/body size matched controls. Grapplers had been exposed to >500 choke events while training for >5 years in a choke-inclusive sport. Exclusion criteria were recent TBI or deficits from a past TBI or stroke. Bilateral ultrasound measurement of the CIMT was performed, and blood was collected for quantitative analysis of four brain injury markers. Subgroup analyses were performed within the Grappler group to account for blunt head trauma as a possible confounder.

RESULTS

There was no overall difference in CIMT measurements between Grapplers (mean 0.55 mm, SD 0.07) and Controls (mean 0.57 mm, SD 0.10) p = 0.498 [95% CI -0.04-0.08], nor were there CIMT differences between Grappler subgroups of blunt Trauma and No-Trauma. There were no significant differences in any biomarkers comparing Grapplers and Controls or comparing Grappler subgroups of Trauma and No-Trauma.

CONCLUSION

This study found no significant difference in CIMT and serum brain injury biomarkers between controls and grapplers with extensive transient choke experience, nor between grapplers with extensive past blunt head trauma and those without.

Articulation Rate, Pauses, and Disfluencies in Professional Fighters: Potential Speech Biomarkers for Repetitive Head Injury

OBJECTIVE

As part of a larger study dedicated to identifying speech and language biomarkers of neurological decline associated with repetitive head injury (RHI) in professional boxers and mixed martial artists (MMAs), we examined articulation rate, pausing, and disfluency in passages read aloud by participants in the Professional Athletes Brain Health Study.

SETTING

A large outpatient medical center specializing in neurological care.

PARTICIPANTS, DESIGN, AND MAIN MEASURES

Passages read aloud by 60 boxers, 40 MMAs, and 55 controls were acoustically analyzed to determine articulation rate (the number of syllables produced per second), number and duration of pauses, and number and duration of disfluencies in this observational study.

RESULTS

Both boxers and MMAs differed from controls in articulation rate, producing syllables at a slower rate than controls by nearly half a syllable per second on average. Boxers produced significantly more pauses and disfluencies in passages read aloud than MMAs and controls.

CONCLUSIONS

Slower articulation rate in both boxers and MMA fighters compared with individuals with no history of RHI and the increased occurrence of pauses and disfluencies in the speech of boxers suggest changes in speech motor behavior that may relate to RHI. These speech characteristics can be measured in everyday speaking conditions and by automatic recognition systems, so they have the potential to serve as effective, noninvasive clinical indicators for RHI-associated neurological decline.

Examining the occurrence and outcomes of concussion and mTBI in mixed martial arts athletes: a systematic review

INTRODUCTION

Mixed martial arts (MMA) is a sport growing in popularity around the world. However, many individuals participate in the sport with little understanding of the potential short- and long-term consequences of injuries sustained while participating. Specifically, individuals are placed at a high risk of minor traumatic brain injury (mTBI) and concussive episodes as a result of head injuries incurred during training and competition.

AIMS

The current review aimed to examine the literature surrounding the occurrence and outcomes of mTBI in MMA athletes to gain a better understanding of these consequences.

METHODS

Twenty-five studies were identified within the current review, of which 14 examined occurrence of mTBI within the sport setting, and elevenidentified outcomes of injury.

RESULTS

Overall, studies found that MMA athletes experienced mTBI and concussion to a greater extent than athletes in other sports. Deficits in memory, reaction time and processing speed were identified following occurrence of mTBI; however, several gaps in outcome measurement were identified within the current literature, including a lack of focus on speech and language outcomes.

CONCLUSION

Future research should examine a wider variety of outcomes to provide a clearer understanding of the consequences of participating in the sport.

Alternative Model for Physical Activity: Active Video Games Lead to High Physiological Responses

Purpose: This study aimed to i) investigate the physiological and perceptual responses to two different active video games (AVGs), ii) compare the physiological and perceptual responses to AVGs with those encountered during classic exercise and daily sedentary routines, and iii) compare the examined variables between the sexes. Methods: Forty-three (n = 22 male, n = 21 female) volunteers participated in the study and were tested in five different conditions (resting, watching television (TV), brisk walking, AVG dancing, and AVG fighting). Oxygen consumption (VO₂) and heart rate (HR) were measured continuously, whereas energy expenditure (EE) and metabolic equivalent (MET) were calculated. Rating of perceived exertion (RPE) and enjoyment scores were recorded. Results: AVG dancing and AVG fighting significantly increased VO₂, MET, EE, and HR compared with brisk walking, resting, and watching TV. Comparing with brisk walking the AVG dancing yielded similar RPE and higher enjoyment scores. However, the highest physiological responses, RPE, and enjoyment scores were obtained during AVG fighting. There were significant sex x condition interactions for VO₂, MET, EE, and HR. VO₂, MET, and EE were significantly higher in males for all conditions, whereas HR was significantly higher in females. The mean EE values during AVG fighting and AVG dancing were 13.12 ± 2.2 kcal.min^-1 and 9.69 ± 2.0 kcal.min^-1, respectively in males, and 9.31 ± 1.9 kcal.min^-1 and 7.07 ± 1.3 kcal.min^-1, respectively in females. Conclusions: AVG dancing (MET >7) and AVG fighting (MET >9) are enjoyable, vigorous physical activities that can be recommended as an alternative home-based physical activity.

Concussion vs. resignation by submission: Technical–tactical behavior analysis considering injury in mixed martial arts

This research study verified the technical–tactical actions during the mixed martial arts (MMA) fights to generate serious enough injury to stop the MMA round, determining technical-tactical potential risk factors for injury in official MMA combats, according to Concussion or Resignation per Submission. A total of 990 rounds with concussions and 627 resignations per submission were considered with severe injury (i.e., a fight ended by a doctor or referee). All injuries were diagnosed and managed by attending ringside physicians during the MMA fights and rounds and had a continuous technical–tactical behavior analysis, p ≤ 0.05. The leading cause of concussion was due to head trauma (~90%), with higher dependence on head strikes scored actions. Comparisons between Concussion and Resignation per Submission combats demonstrated differences between distance head strikes actions [13(6,25) vs. 9(4,18) frequencies], clinch head strikes actions [1(0;4) vs. 1(0;3) frequencies], ground head strikes actions [1(0;8) vs. 2(0;10) frequencies] and takedowns actions [0(0;1) vs. 1(0;2) frequencies]. This information may provide significant evidence regarding the doctor stoppage in concussion combats and when it could be called by officials supervising MMA.

Frequency, Method, Intensity, and Health Sequelae of Sexual Choking Among U.S. Undergraduate and Graduate Students

Although sexual choking is now prevalent, little is known about how people engage in choking in terms of frequency, intensity, method, or potential health sequelae. In a campus-representative survey of undergraduate and graduate students, we aimed to: (1) describe the prevalence of ever having choked/been choked as part of sex; (2) examine the characteristics of choking one's sexual partners (e.g., age at first experience, number of partners, frequency, intensity, method); (3) examine the characteristics of having been choked during sex; and (4) assess immediate responses of having been choked including the extent to which frequency and method (e.g., hand, ligature, limb) of having been choked predicts the range of responses endorsed by participants. A total of 4254 randomly sampled students (2668 undergraduate, 1576 graduate) completed a confidential online survey during Spring 2021. The mean age of first choking/being choked was about 19, with more undergraduates than graduate students reporting first choking/being choked in adolescence. Women and transgender/gender non-binary participants were significantly more likely to have been choked than men. Participants more often reported the use of hands compared to limbs or ligature. Common responses to being choked were pleasurable sensations/euphoria (81.7%), a head rush (43.8%), feeling like they could not breathe (43.0%), difficulty swallowing (38.9%), unable to speak (37.6%), and watery eyes (37.2%). About 15% had noticed neck bruising and 3% had lost consciousness from being choked. Greater frequency and intensity of being choked was associated with reports of more physical responses as was use of limb (arm, leg) or ligature.

Cervical Artery Dissections and Ischemic Strokes Associated with Vascular Neck Compression Techniques (Sportive Chokes)

BACKGROUND

Strangulation as a fight-finishing maneuver in combat sports, termed "choking" in that context, occurs worldwide millions of times yearly. This activity can be trained safely, but devastating injuries can occur.

OBJECTIVE

Our aim was to present a case series of cervical artery dissections and ischemic strokes associated with sportive choking. Sharing these cases is meant to draw awareness, to assist emergency physicians in caring for these athletes, and to provide a platform for further research.

METHODS

Institutional Review Board approval was obtained. Participants consented for medical information transfer and anonymous academic reproduction. The minimum medical record information necessary for inclusion was a report of diagnosis-confirming advanced imaging. Participants were contacted for primary information in addition to what the medical records could provide and to confirm some information in the record (e.g., pertinent medical history, demographic characteristics, choking event description, medical care, and commentary on their current health). Medical records and additional first-hand information were reviewed and participants were included if they had a diagnosed dissection or stroke likely associated with a sportive choke.

RESULTS

Ten cases met all criteria for inclusion. There were 5 cases of carotid artery dissection, 3 cases of vertebral artery dissection, and 2 cases of ischemic stroke without dissection. Nine of 10 participants survived and 3 of 10 have returned to submission grappling training.

CONCLUSIONS

Cervical artery dissections and ischemic strokes can occur in association with sportive choking. Emergency physicians must be aware of the widespread nature of this activity and must be vigilant in approaching management of patients with symptoms consistent with these injuries.

Approach considerations for the management of strangulation in the emergency department

Patients with a history of strangulation present to the emergency department with a variety of different circumstances and injury patterns. We review the terminology, pathophysiology, evaluation, management, and special considerations for strangulation injuries, including an overview of forensic considerations and legal framework for strangulation events.

Analysis of the fight-ending chokes in the history of the Ultimate Fighting Championship™ mixed martial arts promotion

OBJECTIVE

Knowledge of sportive chokes is vital to the practice of Sports Medicine when providing care at mixed martial arts and submission grappling events. This is a descriptive analysis of fight-ending chokes to help provide data on the topic not previously presented.

METHODS

An analysis was done on every fight-ending choke in the history of the UFC™ mixed martial arts promotion. Investigators focused on the frequency of chokes, types of chokes, handedness of the chokes, and whether chokes resulted in loss of consciousness. This analysis was done using existing fight outcome reports and video analysis of every choke that ended a fight in UFC™ history.

RESULTS

During the study period there were 904 such chokes, comprising 15.5% of fight outcomes and 76.2% of grappling submissions. The makeup of right (50.1%) and left (49.9%) handedness of the chokes has been essentially identical (χ2 [1] = 0.0011, p =.947, phi =.00). Most of the fight-ending chokes culminated in voluntary submission; however, 11% resulted in loss of consciousness. The rear naked choke (RNC) was significantly more frequent than other chokes, comprising 49.1% of the total choke finishes; 19 other choke types accounted for the remaining 50.9%.

CONCLUSION

Fight-ending chokes have been common in MMA. Many types of chokes have successfully ended UFC™ fights, with the RNC accounting for almost half of fight-ending chokes. Loss of consciousness occurred in 11% of fight-ending chokes. Right and left handed chokes were utilized equally.

Craniofacial and traumatic brain injuries in mixed martial arts

Objective: Mixed-Martial-Arts (MMA) has witnessed a rapid growth over the recent years. This study aims to explore the patterns and trends of head injuries in MMA.Design: Descriptive epidemiological study.Setting: Ringside physician reports of the Ultimate Fighting Championship (UFC) fights between 2016 and 2019 (inclusive) were screened. Data were extracted from the Nevada State Athletic Commission (NSAC) database. Play-by-play video analysis was also conducted.Participants: UFC fighters involved in fights sanctioned by the NSAC, between 2016 and the end of 2019 (N = 816).Independent variables: Sex, location of head injury, type of head injury, injury mechanism, number of significant head strikes, type of finish, and weight division.Main outcome measures: Head injury rates were calculated. A one-way analysis of variance (ANOVA) was used to explore any statistically significant differences between injury rates of different locations, types, and types of finishes. An independent t-test was used to determine whether any significant differences existed between the two sexes, and a Joinpoint regression analysis was used to determine the statistical significance of the trends of head injury rates across different weight divisions. P-values <0.05 were considered significant (95% CI).Results: A total of 288 head injuries in 408 fights were recorded during our study period. Head injury rate constituted 35 injuries per 100 athletic-exposures (AE) in sanctioned fights. Traumatic brain injuries (TBI) were the most common type of injury, with a rate of 16 per 100AE, significantly greater than that of fractures (p = 0.003). Males had a head injury rate of 37 per 100AE, higher than that of females which was 23 per 100AE. Technical Knockout (TKO)/ Knockout(KO) was the type of finish with the highest rate of head injuries, significantly greater than that of decision or submission (p < 0.001). In general, head injury rates were higher as weight divisions increased.Conclusion: Head injuries are prevalent in MMA. Preventive measures need to be implemented to ensure fighter safety and limit injury risk.

Elevated cerebral perfusion and preserved cognition in elite Brazilian Jiu-Jitsu athletes: Evidence for neuroprotection

Brazilian Jiu-Jitsu (BJJ) is a popular martial art that exposes participants to recurrent intermittent asphyxiation due to controlled application of neck chokes. To what extent the sport impacts the regulation of cerebral blood flow (CBF) and cognition has not been examined. This study compared eleven elite Brazilian Jiu-Jitsu athletes (aged 30 ± 8 y) who trained 12 ± 6 hours/week for 8 ± 4 years against eleven cardiorespiratory fitness (CRF)- and age-matched controls. Internal carotid (ICA) and vertebral artery (VA) blood flow were measured via duplex ultrasound to determine global cerebral blood flow (gCBF). Mild cognitive impairment and sub-domains of memory, attention/concentration/visual motor coordination, and executive function were determined by psychometric testing. There was no evidence of mild cognitive impairment in the athletes, and cognitive function was comparable between groups (all p > 0.05). In contrast, resting gCBF was selectively elevated in the athletes (741 ± 186 mL∙min^-1 vs. 573 ± 166 mL∙min^-1 , p = 0.037) due to combined differences in ICA (+65 mL∙min^-1 , p = 0.079) and VA (+19 mL∙min^-1 , p = 0.277) flow. In conclusion, the sustained elevation in resting cerebral perfusion provides preliminary evidence for adaptive neuroprotection that is independent of CRF and likely mediated by choke-induced cerebral preconditioning and/or lifelong exposure to BJJ-specific high-intensity interval training.

Maxillofacial Trauma in the Ultimate Fighting Championship

PURPOSE

The Ultimate Fighting Championship (UFC) is an American mixed martial art (MMA) company. This study aims to characterize patterns and trends of maxillofacial injuries in MMA.

MATERIALS AND METHODS

The study design is a retrospective cohort study. Study sample consisted of fighters that suffered injuries during the matches from January 2015 to December 2019 (N = 259). The Athletic Commissions and corresponding fighting regulatory departments from 16 states and 24 countries were screened for medical reports released by UFC ringside physicians. Predictor variables were sex, weight division, injury location, injury type, and fight outcome (i.e., Technical Knockout/Knockout, Submission, Decision). Primary outcome variables were need for medical suspension and duration of medical suspension, secondary outcome variable was frequency of injury. Chi-square test was used to determine any statistical significance between predictor variables. One-way analysis of variance was used to determine any statistically significant differences between medical suspension times, sex, injury location, type of injury, weight divisions and fight outcome throughout the years. P value less than .05 (95% confidence interval [CI]) was considered statistically significant.

RESULTS

A total of 259 fighters suffered injuries. Of the 319 total injuries, 291 (91.2%) occurred in male fighters, and 28 (8.8%) in females. Middle facial third injuries were the most common for both males and females; lower facial third injuries were proportionally similar. The male weight division with the longest medical suspensions were the light heavyweight (110.68 days) and welterweight (108.25 days) (P < .10166); the female weight division with the longest medical suspension was strawweight (88.92 days) and shortest was bantamweight (81.75 days) (P < .921123).

CONCLUSIONS

Upper and midface trauma was predominant with fractures concentrated in the light heavyweight and welterweight divisions. Medical suspensions duration were longer in the light heavyweight and welterweight divisions.

Severe Suicidality in Athletes with Chronic Traumatic Encephalopathy: A Case Series and Overview on Putative Ethiopathogenetic Mechanisms

Chronic traumatic encephalopathy (CTE) results from repetitive brain injuries and is a common neurotraumatic sequela in contact sports. CTE is often accompanied by neuropsychiatric symptoms, which could escalate to suicidal ideation (SI) and suicidal behaviour (SB). Nevertheless, fairly limited emphasis about the association between suicidality and CTE exists in medical literature. Here, we report two cases of retired professional athletes in high contact sports (boxing and ice hockey) who have developed similar clinical trajectories characterized by progressive neuropsychiatric symptoms compatible with a CTE diagnosis and subsequent SB in its severe forms (medical serious suicide attempt (SA) and completed suicide). In addition to the description of outlining clinical, neuropsychological, neuroimaging, and differential diagnosis elements related to these cases, we also hypothesized some mechanisms that might augment the suicide risk in CTE. They include those related to neurobiological (neuroanatomic/neuroinflammatory) dysfunctions as well as those pertaining to psychiatry and psychosocial maladaptation to neurotraumas and retirement from professional competitive activity. Findings described here can provide clinical pictures to improve the identification of patients with CTE and also potential mechanistic insights to refine the knowledge of eventual severe SB development, which might enable its earlier prevention.

The neuropsychological outcomes of non-fatal strangulation in domestic and sexual violence: A systematic review

This systematic review draws together evidence from the literature for the pathological, neurological, cognitive, psychological, and behavioural outcomes of non-fatal strangulation in domestic and sexual violence. A systematic search of PubMed, PsycINFO, CINHAL, Proquest, ASSIA, Web of Science, WestLaw, Open Grey, and Ethos was conducted, with no date limits set, to identify eligible studies. Thirty empirical, peer-reviewed studies were found which met the inclusion criteria. Pathological changes included arterial dissection and stroke. Neurological consequences included loss of consciousness, indicating at least mild acquired brain injury, seizures, motor and speech disorders, and paralysis. Psychological outcomes included PTSD, depression, suicidality, and dissociation. Cognitive and behavioural sequelae were described less frequently, but included memory loss, increased aggression, compliance, and lack of help-seeking. However, no studies used formal neuropsychological assessment: the majority were medical case studies or based on self-report. Furthermore, few authors were able to control for possible confounds, including other physical violence and existing psychosocial difficulties. There is therefore a need for further neuropsychological research, focusing on cognitive and behavioural outcomes, using standardized tools, and control groups where possible. This is urgent, given societal normalization of strangulation, and legal systems which often do not reflect the act's severity and its consequences.

The safety of sportive chokes: a cross-sectional survey-based study

Objectives: Sportive choking or strangling, known as a 'choke' in the combat sports community, is the practice of compressing the jugular veins and carotid arteries to threaten unconsciousness by lowering cerebral perfusion pressure. This is commonly practiced within combat sports and police/military combatives. The safety profile of sportive choking is underrepresented in the literature. The authors sought to explore the safety of sportive chokes. Methods: A convenience sample of visitors to two combat sports internet forums completed an anonymous web-based survey on choking experience and related symptoms. Descriptive statistics were used to describe the obtained data. Bivariate analysis was performed to elaborate on relationships between grappling experience and the number of times choked, between the number of times choked with pre-syncope/syncope, and between the duration of symptoms and the number of times choked with pre-syncope/syncope. Results: Overall, 4421 individuals completed the survey. One hundred and fourteen were excluded, leaving 4307 analyzed respondents. Ninety-four percent were male, 89.2% were ages 18-44 years. Seventy-nine percent had >1 year of grappling experience and 30% had >5 years. Of the 4307, 1443 (33.5%) reported being choked >500 times, 3257 (75.7%) have been choked to near-syncope, and 1198 (27.8%) have been choked unconscious. Two of the 4307 (0.05%) reported ongoing symptoms from chokes. Of the respondents, 94.3% felt applying a choke would be a safe and effective way to control a street fight; 83.6% felt that vascular neck restraint, the police combative equivalent of sportive choking, would be appropriate as an alternative escalation of force option. Conclusion: Based on a convenience sample of 4307 respondents' self-reported data, sportive choking appears to be safe. Only 0.05% experienced ongoing symptoms, which were likely not related to brain ischemia.

Bibliometric Analysis of Chronic Traumatic Encephalopathy Research from 1999 to 2019

Research on chronic traumatic encephalopathy (CTE) has increased over the past two decades. However, few studies have statistically analyzed these publications. In this work, we conducted a bibliometric analysis of studies on CTE to track research trends and highlight current research hotspots. Relevant original articles were obtained from the Web of Science Core Collection database between 1999 and 2019. CiteSpace and VOSviewer software were used to perform analysis and visualization of scientific productivity and emerging trends. Our results show that the publications related to CTE dramatically increased from four publications in 1999 to 160 publications in 2019. The United States dominated this field with 732 publications (75.934%), followed by Canada with 88 publications (9.129%). Most of related publications were published in the journals with a focus on molecular biology, immunology, neurology, sports and ophthalmology, as represented by the dual-map overlay. A total of 11 major clusters were explored based on the reference co-citation analysis. In addition, three predominant research topics were summarized by clustering high-frequency keywords: epidemiological, clinical and pathological studies. The research frontiers were the diagnosis of diseases using new neuroimaging techniques, and the investigation of the molecular mechanism of tau aggregation. This study provides researchers with valuable guidance in the selection of research topics.