Abstract
Background:
Brazilian jiu-jitsu (BJJ) is a grappling-based martial art that can lead to injuries both in training and in competition. There is a paucity of data regarding injuries sustained while training in BJJ, in both competitive and noncompetitive jiu-jitsu athletes.
Hypothesis:
We hypothesize that most BJJ practitioners sustain injuries to various body locations while in training and in competition. Our primary objective was to describe injuries sustained while training for BJJ, both in practice and in competition. Our secondary objectives were to classify injury type and to explore participant and injury characteristics associated with wanting to quit jiu-jitsu after injury.
Study Design:
Descriptive epidemiology study.
Methods:
We conducted a survey of all BJJ participants at a single club in Hamilton, Ontario, Canada. We developed a questionnaire including questions on demographics, injuries in competition and/or training, treatment received, and whether the participant considered discontinuing BJJ after injury.
Results:
A total of 70 BJJ athletes participated in this study (response rate, 85%). Ninety-one percent of participants were injured in training and 60% of competitive athletes were injured in competitions. Significantly more injuries were sustained overall for each body region in training in comparison with competition (P < 0.001). Two-thirds of injured participants required medical attention, with 15% requiring surgery. Participants requiring surgical treatment were 6.5 times more likely to consider quitting compared with those requiring other treatments, including no treatment (odds ratio [OR], 6.50; 95% CI, 1.53-27.60). Participants required to take more than 4 months off training were 5.5 times more likely to consider quitting compared with those who took less time off (OR, 5.48; 95% CI, 2.25-13.38).
Conclusion:
The prevalence of injury is very high among BJJ practitioners, with 9 of 10 practitioners sustaining at least 1 injury, commonly during training. Injuries were primarily sprains and strains to fingers, the upper extremity, and neck. Potential participants in BJJ should be informed regarding significant risk of injury and instructed regarding appropriate precautions and safety protocols.
Clinical Relevance:
Clinicians should be aware of the substantial risk of injury among BJJ practitioners and the epidemiology of the injuries as outlined in this article.
Keywords: martial arts, Brazilian jiu-jitsu, injuries, fractures, orthopaedic surgery
Brazilian jiu-jitsu (BJJ) is a grappling-based martial art with roots in prewar Kodokan Judo.8,13 BJJ has undergone modifications and refinements over the years and has been increasing in popularity within North America and globally over the past 20 years.8,13 As a grappling-based sport it involves submission wrestling, including chokes/strangles and joint locks. Additionally, BJJ incorporates aggressive takedowns from standing and self-defense techniques to cause the opponent to submit or exit the situation if in a state of self-defense.
A number of studies exist regarding the epidemiology of injuries sustained while training in judo, karate-do, taekwondo, mixed martial arts, and BJJ competitions2,7,9-11,15; however, there is a paucity of data on injuries sustained during training in BJJ both in the competitive and noncompetitive athlete. Previous studies in other martial arts have identified that injuries are more commonly sustained in training than competition.4,5,14 Additionally, the vast majority of injuries (78%) sustained in BJJ competitions are orthopaedic injuries, many of which require medical attention or surgical intervention.15
We undertook a survey of jiu-jitsu practitioners to understand the injury patterns and prevalence of injuries sustained in BJJ training, practice, and competition. Our primary objective was to determine the prevalence of injuries sustained during jiu-jitsu training and competition. Our secondary objectives were to describe the types of injuries, to determine which participant and injury characteristics are associated with desire to discontinue jiu-jitsu after injury, and which characteristics are associated with requiring surgery for an injury.
Methods
Questionnaire Development
We developed a questionnaire using focus groups, key informants, and the previous literature. Focus groups consisted of jiu-jitsu practitioners as well as orthopaedic surgeons treating jiu-jitsu injuries. We also generated items from a Medline search of articles published from 1966 to 2017 using text words “Brazilian jiu-jitsu,” “submission wrestling,” “jiu-jitsu,” “judo,” “martial arts,” and “mixed martial arts.” These were used to improve the data from our focus group item generation. We used a sample to redundancy approach until no new items for the questionnaire emerged.
We pretested the questionnaire with an independent group of 2 orthopaedic surgeons and 3 martial artists, including 2 jiu-jitsu practitioners for face and content validity. This involved evaluation of whether the questionnaire as a whole appeared to adequately capture the range of potential injuries sustained while undergoing jiu-jitsu training and competition and whether individual questions adequately affected the 4 broad domains of jiu-jitsu training and experience (beginner, advanced beginner, midlevel, and advanced practitioner). The informants also commented on the clarity and comprehensiveness of the questionnaire.
The final questionnaire contained 26 questions regarding demographics, timing of injuries, injury characteristics, treatment received, and whether participants considered quitting BJJ after injury (see the appendix, available in the online version of this article).
Questionnaire Administration
We surveyed all jiu-jitsu practitioners of a single club in Hamilton, Ontario, Canada, during 2016. Members of the club each received a package with a copy of the survey, a personalized cover letter, and a return envelope. No monetary incentives or prenotification telephone calls were used for this survey, and attempted follow-up of nonresponders was done on 2 occasions via email or in-person. This study was reviewed and approved by the Hamilton Integrated Research Ethics Board (No. 2007). All practitioners surveyed received a letter of information and consent form. Signed consent was obtained for all surveys, questionnaire completion was voluntary, and individual responses were kept anonymous and confidential.
Statistical Analysis
Our primary analysis was descriptive. We summarized categorical and dichotomous variables as frequencies and percentages. Overall prevalence and characteristics of injuries occurring in training and in competition were assessed.
Chi-square test was performed to compare prevalence of injuries sustained during competition versus training as well as if injury location differed between competition and training. Additionally, we conducted unadjusted logistic regression analyses to evaluate the association between selected demographic and injury patterns and those who considered quitting jiu-jitsu as a result of their injuries as a dependent variable. Exploratory binary logistic regression analyses were also performed to evaluate the association between selected demographic and injury patterns and those who required surgical treatment for their injury as a dependent variable. Findings were reported as unadjusted odds ratios (ORs) with 95% CIs.
To detect a 20% difference in injuries sustained during competition versus training, 73 participants (2-tailed α = 0.05; 80% power) were required.
Results
Participant Characteristics
Of the 82 jiu-jitsu practitioners approached to complete the survey, 70 participated and returned their completed survey (response rate 85%). The majority of respondents were male (90.0%), older than 30 years (58.5%), and junior trainees (white belts [37.2%] or blue belts [42.9%]). Please see Table 1 for full demographic information.
Table 1.
Participant characteristics for recreational and competitive jiu-jitsu athletes
| Demographic Variable | Recreational Athletes (N = 35), n (%) | Competitive Athletes (N = 35), n (%) | All Athletes (N = 70), n (%) |
|---|---|---|---|
| Age (years) | |||
| 18-25 | 8 (22.9) | 12 (34.3) | 20 (28.6) |
| 25-29 | 4 (11.4) | 5 (14.3) | 9 (12.9) |
| 30-34 | 6 (17.1) | 5 (14.3) | 11 (15.7) |
| 35-39 | 7 (20.0) | 5 (14.3) | 12 (17.1) |
| 40-44 | 5 (14.3) | 4 (11.4) | 9 (12.9) |
| 45-49 | 3 (8.6) | 2 (5.7) | 5 (7.1) |
| 50-54 | 1 (2.9) | 0 | 1 (1.4) |
| 55+ | 1 (2.9) | 2 (5.7) | 3 (4.3) |
| Sex | |||
| Male | 30 (85.7) | 33 (94.3) | 63 (90.0) |
| Female | 5 (14.3) | 2 (5.7) | 7 (10.0) |
| Belt rank | |||
| White belt (0-6 months) | 10 (28.6) | 0 | 10 (14.3) |
| White belt (6+ months) | 9 (25.7) | 7 (20.0) | 16 (22.9) |
| Blue belt | 11 (31.4) | 19 (54.3) | 30 (42.9) |
| Purple belt | 3 (8.6) | 4 (11.4) | 7 (10.0) |
| Brown belt | 0 | 3 (8.6) | 3 (4.3) |
| Black belt | 2 (5.7) | 2 (5.7) | 4 (5.7) |
| Years trained | |||
| 0-1 | 10 (28.6) | 3 (8.6) | 13 (18.6) |
| 1-3 | 10 (28.6) | 6 (17.1) | 16 (22.9) |
| 3-5 | 4 (11.4) | 8 (22.9) | 12 (17.1) |
| 5-7 | 5 (14.3) | 8 (22.9) | 13 (18.6) |
| 8+ | 6 (17.1) | 10 (28.6) | 16 (22.9) |
| Hours spent training per week | |||
| 0-2 | 2 (5.7) | 0 | 2 (2.9) |
| 3-5 | 24 (68.6) | 17 (48.6) | 41 (58.6) |
| 6-8 | 9 (25.7) | 11 (31.4) | 20 (28.6) |
| 9-11 | 0 | 2 (5.7) | 2 (2.9) |
| 12+ | 0 | 5 (14.3) | 5 (7.1) |
| Injured in training | 30 (85.7) | 34 (97.1) | 64 (91.4) |
| Injured in competition | 0 | 21 (60.0) | 21 (60.0) |
Injuries Sustained
Training Injuries
Of those completing the survey, 64 (91.4%) were injured while in training (Table 2). The majority of injuries were sprains (61.4%) or strains (57.1%). Significant injuries, including fractures (18.6%), lacerations (12.9%), dislocations (11.4%), and concussions (7.1%), were also relatively common.
Table 2.
Injury characteristics a
| Injury Characteristic | Training Injury (N = 70), n (%) | Competition Injury (N = 35), n (%) |
|---|---|---|
| Any injury | 64 (91.4) | 21 (60.0) |
| Head/Neck/Face injury | 45 (64.3) | 7 (20.0) |
| Neck | 33 (50.8) | 3 (8.6) |
| Ears | 22 (33.8) | 1 (2.9) |
| Face | 16 (24.6) | 3 (8.6) |
| Mouth | 10 (15.4) | 2 (5.7) |
| Cranium | 7 (10.8) | 1 (2.9) |
| Nose | 6 (9.2) | 1 (2.9) |
| Eyes | 5 (7.7) | 1 (2.9) |
| Upper extremity injury | 52 (74.3) | 15 (42.9) |
| Fingers | 34 (52.3) | 5 (14.3) |
| Shoulder | 32 (49.2) | 10 (28.6) |
| Elbow | 25 (38.5) | 5 (14.3) |
| Wrist | 18 (27.7) | 2 (5.7) |
| Forearm | 4 (6.2) | 2 (5.7) |
| Palm | 3 (4.6) | 1 (2.9) |
| Arm | 2 (3.1) | 1 (2.9) |
| Core injury | 34 (48.6) | 6 (17.1) |
| Ribs | 26 (40.0) | 3 (8.6) |
| Chest | 7 (10.8) | 2 (5.7) |
| Pelvis | 6 (9.2) | 0 |
| Abdomen | 5 (7.7) | 2 (5.7) |
| Spine | 5 (7.7) | 1 (2.9) |
| Lower extremity injury | 50 (71.4) | 10 (28.6) |
| Knee | 33 (50.8) | 3 (8.6) |
| Ankle | 24 (36.9) | 4 (11.4) |
| Toes | 21 (32.3) | 4 (11.4) |
| Groin | 12 (18.5) | 1 (2.9) |
| Foot | 11 (16.9) | 2 (5.7) |
| Hip | 11 (16.9) | 1 (2.9) |
| Thigh | 2 (3.1) | 1 (2.9) |
| Midfoot | 2 (3.1) | 1 (2.9) |
| Injury type | ||
| Sprain | 43 (61.4) | 11 (31.4) |
| Strain | 40 (57.1) | 9 (25.7) |
| Contusion | 32 (45.7) | 3 (8.6) |
| Unspecified joint injury | 31 (44.3) | 5 (14.3) |
| Fracture | 13 (18.6) | 5 (14.3) |
| Laceration | 9 (12.9) | 1 (2.9) |
| Dislocation | 8 (11.4) | 6 (17.1) |
| Concussion | 5 (7.1) | 1 (2.9) |
Participants can select more than 1 response; percentages do not add to 100%.
Competition Injuries
Of the 35 participants who participated in BJJ competitions, 60.0% were injured in competition (Table 2). Similar to injuries sustained in training, sprains (31.4%) and strains (25.7%) were the most common injuries sustained in competition. See Table 2 for further injury details. In contrast to injuries sustained during training, shoulder injuries were the most common specific injury location (28.6%), followed by fingers and elbows (both 14.3%).
Competition Injuries Compared With Training Injuries
The setting of the most severe injury for 59 (90.8%) of the injured jiu-jitsu practitioners was while in training or practice in the jiu-jitsu club, while only 6 (9.2%) sustained their most severe injury while in competition. There was a significantly higher prevalence of injuries in training in comparison with competition (P < 0.001). Additionally, there was a significantly higher prevalence of injuries in training for each body region (head/neck/face P < 0.001; upper extremity P = 0.0016; core P = 0.0018; lower extremity P < 0.001).
Treatment
Forty-four of 65 respondents with injuries (67.7%) required medical attention for their injury (Table 3). Ten respondents (15.4%) required surgery for their injury. Over half (55.4%) of injured respondents were advised by a physician to take time off of BJJ training. Nearly half (46.1%) stated that the injury has had a negative impact on their life. Thirteen (20.0%) of injured BJJ practitioners thought about quitting BJJ as a result of their injury but did not. See Table 3 for full details on types of treatment.
Table 3.
Treatment characteristics
| Treatment | Number (%) a |
|---|---|
| Required medical attention | 44 (67.7) |
| Surgery | 10 (15.4) |
| Physical therapy/Rehabilitation | 38 (58.5) |
| Immobilization | 17 (26.2) |
| Chiropractic care | 11 (16.9) |
| Prescribed medication | 31 (47.7) |
| NSAID | 17 (26.2) |
| Acetaminophen | 8 (12.3) |
| Marijuana | 3 (4.6) |
| Narcotic analgesic | 3 (4.6) |
| Nonprescribed medication | 42 (64.6) |
| NSAID | 23 (35.4) |
| Acetaminophen | 9 (13.8) |
| Marijuana | 9 (13.8) |
| Narcotic analgesic | 1 (1.5) |
| Medically advised to take time off BJJ | 36 (55.4) |
| Time off from BJJ | 55 (84.6) |
| <1 month | 25 (38.5) |
| 1-3 months | 16 (24.6) |
| 4-6 months | 6 (9.2) |
| 8-12 months | 3 (4.6) |
| >12 months | 5 (7.7) |
BJJ, Brazilian jiu-jitsu; NSAID, nonsteroidal anti-inflammatory drug.
N = 65 participants with injuries.
Factors Associated With Desire to Stop BJJ After Injury
Treatment type and amount of time required off training were significantly associated with desire to quit after injury. Participants requiring surgical treatment were 6.5 times more likely to consider quitting compared with those who had other treatments, including no treatment (OR, 6.50; 95% CI, 1.53-27.60). Participants taking more than 4 months off training were 5.5 times more likely to consider quitting compared with those who took less time off (OR, 5.48; 95% CI, 2.25-13.38). There was no statistical relationship between level of training, number of years training, or age associated with desire to discontinue training after injury (Table 4).
Table 4.
Binary logistic regression of characteristics associated with considering quitting BJJ (unadjusted)
| Characteristic | Unadjusted OR (95% CI) | P |
|---|---|---|
| Level of BJJ | ||
| Beginner (White) | REF | |
| Advanced (Blue-Black) | 2.26 (0.56-9.09) | 0.253 |
| Training years | ||
| 1-3 | REF | |
| >3 | 2.80 (0.70-11.2) | 0.148 |
| Age (years) | ||
| 18-29 | REF | |
| 30-44 | 0.404 | 0.368 |
| 45+ | 1.167 | 0.864 |
| Injury type | ||
| Fracture | 2.94 (0.79-10.88) | 0.107 |
| Any other a or none | REF | |
| Treatment | ||
| Surgery | 6.50 (1.53-27.60) | 0.011 |
| Any other b or none | REF | |
| Time off of training | ||
| ≤4 months | REF | |
| >4 months | 5.48 (2.25-13.38) | <0.001 |
BJJ, Brazilian jiu-jitsu; OR, odds ratio; REF, reference category.
Other injury types include sprain, strain, contusion, laceration, and joint injury.
Other treatments include physical therapy, rehabilitation, chiropractic care, and immobilization.
Factors Associated With Requiring Surgical Treatment After Injury
Participants taking more than 4 months off were 19 times more likely to have had surgical intervention for their injury (OR, 19.33; 95% CI, 2.91-128.50). We did not find evidence that belt level, number of years training, age, injury type, or training versus competition injury was significantly associated with requiring surgery; however, this analysis was exploratory in nature (Table 5).
Table 5.
Binary logistic regression of characteristics associated with requiring surgery for an injury (unadjusted)
| Characteristic | Unadjusted OR (95% CI) | P |
|---|---|---|
| Level of BJJ | ||
| Beginner (White) | REF | |
| Advanced (Blue-Black) | 6.43 (0.77-54.03) | 0.087 |
| Training years | ||
| 1-3 | REF | |
| >3 | 7.88 (0.94-66.09) | 0.057 |
| Age (years) | ||
| 18-29 | REF | |
| 30-44 | 1.24 (0.25-6.07) | 0.158 |
| 45+ | 4.33 (0.70-27.01) | 0.116 |
| Injury type | ||
| Fracture | 2.97 (0.72-12.34) | 0.134 |
| Any other a or none | REF | |
| Time off of training | ||
| ≤4 months | REF | |
| >4 months | 19.33 (2.91-128.5) | 0.002 |
| Setting of injury | ||
| Training | REF | |
| Competition | 3.19 (0.50-20.35) | 0.220 |
BJJ, Brazilian jiu-jitsu; OR, odds ratio; REF, reference category.
Other injury types include sprain, strain, contusion, laceration, and joint injury.
Discussion
The primary finding of this survey was that the majority of injuries in BJJ are sustained while in training rather than in competition. We identified that over 90% of jiu-jitsu practitioners surveyed suffered injury while in training and the most severe injuries for the majority of practitioners occurred during training. The most common injuries identified involved the fingers, neck, knee, and shoulder, with the majority of respondents seeking medical or surgical treatment, physical therapy, or rehabilitation. This is in keeping with studies assessing injuries of BJJ athletes that were sustained in martial arts competition. In a descriptive epidemiological study, Scoggin et al15 identified that most injuries in competition were orthopaedic (78%) and most involved the upper extremity—specifically, the elbow. Kreiswirth et al7 found that both the knee and elbow had an equal risk of injury in those BJJ competitions that they observed. A systematic review of judo injuries also identified that most injuries were sprains and strains with the knee, shoulder, and hands/fingers being the most commonly injured body parts.12 However, judo injuries were most commonly associated with standing throws,12 whereas most BJJ matches take place grappling on the ground. With regard to finger injuries, it is very common practice for practitioners to tape their fingers; however, cadaveric studies suggest that this may not prevent flexor tendon injuries.17
One in 5 BJJ practitioners considered discontinuing BJJ as a result of their injury but did not. This is despite the fact that 46% indicated that their injury resulted in a negative impact on their quality of life. Furthermore, most respondents required physical therapy or rehabilitation after injury. This was not significantly associated with a desire to discontinue training. However, an injury that required surgery or more than 4 months off of training did predict those who wanted to quit. It may be that there are positive psychological or physical health benefits inherent in training in BJJ that supersede the negative impact of having an injury.6,13 Using the Well-being Questionnaire, Szabo and Parkin16 have identified that in Shotokan karate practitioners, even 1 week off of training can result in mood disturbances such as depression and anxiety. As well, a systematic review of general effects of martial arts on health status identified a number of studies observing the positive health effects associated with martial arts training.3 Similarly, Ardern et al1 reported that practitioners often returned to their sport after an injury due to a low fear of return and a need to maintain motivation and confidence. This may be indicative of the positive psychological benefits of martial arts training for the practitioner’s overall quality of life and well-being.
Limitations
This study has limitations primarily involving the respondent sample, which came from a single club of BJJ practitioners. Thus, generalizability may be limited to similar settings. Similarly, generalizability may be limited due to the majority of respondents being male (90%). We are also limited by a small number of respondents in this survey, and the self-reported nature of the outcomes. The results of the regression analyses were exploratory in nature and are underpowered. Future larger studies should be conducted that are adequately powered to further explore characteristics associated with wanting to discontinue BJJ and with requiring surgical treatment for an injury. It is possible that recall bias affected some of the respondents’ answers given the retrospective nature of the survey. Also, practitioners who had discontinued BJJ and not returned were not surveyed, which may potentially bias our conclusions. This would have allowed further comparisons of factors associated with wanting to quit and indeed quitting. Strengths of this survey include a large range of trainee skill level, age range, and amount of time performing jiu-jitsu. Other strengths include that our sample comprised BJJ practitioners who both compete and train on a regular basis, as well as those who are noncompetitive, for comparison purposes; and finally, that our survey achieved a high response rate (85%).
Conclusion
The prevalence of injury is very high among BJJ practitioners, with 9 of 10 practitioners sustaining at least 1 injury, commonly during training. Injuries were primarily sprains and strains to the fingers, upper extremity, and neck. Potential participants in BJJ should be informed regarding significant risk of injury and instructed regarding appropriate precautions and safety protocols.
Supplementary Material
Footnotes
The following authors declared potential conflicts of interest: B.A.P. is a consultant for and received research support from Stryker, owns stock in Pfizer, and studies Brazilian Jiu Jitsu at Joslin’s Mixed Martial Arts; G.D.F. is an assistant instructor for the children’s program at Joslin’s Mixed Martial Arts; K.M. is a consultant for OrthoEvidence; Jeff Joslin is the owner of Joslin’s Mixed Martial Arts; and M.B. is a consultant for Smith & Nephew, Stryker, Amgen, Zimmer, Moximed, Bioventus, Merck, Eli Lilly, Sanofi, Conmed, Ferring, and DJO, and received grants from Stryker, Zimmer, Amgen, Smith & Nephew, DePuy, Eli Lilly, and Bioventus.
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