The Most Banned Fighting Techniques in the World — And Why They Keep Getting Restricted

A scissor takedown that broke a champion's leg in 1980. A slam that paralyzed a grappler at a local tournament. An elbow strike so controversial it was illegal for twenty-four years — until last November. These are not abstract rule changes. They are decisions written in injury reports, surgical records, and careers ended too soon.

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Between 2024 and 2026, at least four major combat sports organizations changed which techniques are legal in competition. The ADCC banned scissor takedowns and slams from open tournaments. The WKF prohibited kicking fallen opponents in karate. Meanwhile, MMA went the other direction and legalized the 12-6 elbow after a twenty-four-year ban.

We track 30 competition rule sets across 18 combat sports at Fight Encyclopedia. When a technique's legality changes in one organization, we update it across every technique page where it applies — with the rulebook PDF, the year, and the full history. No other system does this.

Here are the techniques that just got banned or restricted, why the organizations made those decisions, and what the medical evidence actually says.

The kani basami — Japanese for "crab scissors" — is a takedown where the attacker drops beside their opponent and scissors their legs at ankle and knee level, toppling them sideways. It is one of the most spectacular and dangerous techniques in grappling.

The incident that changed everything. At the 1980 All Japan Judo Championships, a competitor executed kani basami against Yasuhiro Yamashita — widely considered the greatest judoka of all time. Yamashita's fibula snapped on impact. The IJF banned the technique immediately, classifying it as kinshi waza (prohibited technique). They have never reconsidered.

The injury mechanism. The scissoring action applies lateral force simultaneously at two points on the leg: behind the ankles and across the front of the knees. This creates a rotational shearing force that the knee joint is not designed to absorb. The medial collateral ligament (MCL) and anterior cruciate ligament (ACL) are the primary structures at risk. Research published in the Journal of Orthopaedic Surgery and Research confirms that lateral impact forces on the knee produce the highest strain on the MCL, followed by the ACL — exactly the vector that kani basami generates. In severe cases, the fibula itself fractures from the direct scissoring impact, as happened to Yamashita.

Recovery from a combined ACL-MCL injury typically requires surgical reconstruction and 9 to 12 months of rehabilitation. According to a 2025 review in Medicina, persistent medial instability following combined ACL-MCL injuries is associated with increased biomechanical stress on any ACL graft and a higher risk of surgical failure. Many athletes never return to competition-level performance. For recreational practitioners, such an injury can permanently alter mobility — affecting walking, running, and daily activities for years.

Where Kani Basami Is Banned — And Where It Is Still Legal

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This is where it gets interesting. The same technique is banned in four major rule sets and legal in four others:

Banned in 4 rule sets:

• IJF (Judo) — since 1980. Yamashita's fibula fracture ended the debate. Classified as kinshi waza and never reconsidered.
• IBJJF (BJJ) — since day one. Inherited judo's ban. Illegal at all belt levels, all ages, gi and no-gi.
• UWW (Wrestling) — banned for decades. Scissors on multiple body parts are prohibited in freestyle and Greco-Roman.
• ADCC (Grappling) — banned 2024-2025. First from open tournaments, then all divisions except adult advanced.

Legal in 4 rule sets:

• Unified MMA — always legal, but rarely used. Even professional fighters respect the injury risk.
• FIAS Sport Sambo — always legal. All takedowns permitted without restriction.
• FIAS Combat Sambo — always legal. All takedowns plus strikes allowed.
• NCAA Folkstyle — legal on a single leg. Figure-four scissors on multiple body parts are prohibited.

Why does sambo still allow it? Sambo's philosophy differs fundamentally from judo's post-1980 approach. The FIAS International Sambo Competition Rules (current edition, originally published 2013) permit all takedown techniques without restriction. Sambo's training methodology emphasizes ukemi (breakfalling) from every angle, including lateral falls that are rare in judo training. Sambo competitors specifically drill receiving scissor-type attacks. The argument is straightforward: the technique itself is not inherently more dangerous than many legal throws — the danger comes from opponents who have never trained to receive it.

This is supported by the competitive record. Kani basami appears regularly at FIAS World Championships without the catastrophic injury rate that prompted judo's ban. The difference is preparation, not the technique.

The Longevity Question

Here is the question that competition rule committees rarely ask publicly: should we optimize rules for the tournament season, or for the athlete's entire life?

A 2024 observational study of international athletes published in PMC found that combat sports are associated with reduced lifespan compared to non-contact sports — though the researchers noted the difference likely involves factors beyond traumatic injuries alone. Separately, research on Brazilian jiu-jitsu injury patterns found that 25.2% of practitioners report at least one concussion during their career, with the prevalence significantly higher at beginner levels (49% at white belt) than advanced levels.

The pattern is consistent across disciplines: beginners get hurt more, because they lack the defensive skills to receive techniques safely. Banning a technique entirely is one solution. Training better breakfalls and defensive awareness is another. Sambo chose the second path. Most other organizations chose the first.

In April 2025, ADCC announced that slams are now illegal in all divisions at ADCC Open tournaments. This was a significant departure for an organization that had historically prided itself on minimal restrictions.

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What changed? The ADCC cited repeated injuries at open-level events — tournaments where competitors range from hobbyists to elite athletes. The skill gap matters enormously. When a purple belt executes a slam, they may lack the control to protect their opponent's head and cervical spine. When that purple belt's opponent is a blue belt who has never been slammed in training, the risk compounds.

The injury mechanism. A slam drives the opponent's body — particularly the head, neck, and spine — into the mat with the full force of gravity plus the attacker's body weight and downward momentum. A narrative review published in PMC (2024) on combat sports cervical spine injuries found that throws, takedowns, and slams cause sudden and intense impacts to the cervical spine, ranging from minor muscle strain to severe conditions requiring surgery. Cervical spine flexion-distraction fractures have been documented in BJJ specifically from slam-type impacts.

The critical detail: slams remain legal at ADCC Trials and World Championships — the events where elite competitors face each other. ADCC's decision was not that slams are inherently too dangerous for grappling. It was that slams are too dangerous for open-level competition where skill gaps make injuries predictable.

This distinction matters. It acknowledges that the same technique can be acceptable at one skill level and unacceptable at another.

Effective January 1, 2026, the World Karate Federation prohibited kicking a fallen opponent — only hand techniques are now allowed in such situations. This change targets a specific scenario: a competitor who has been swept or knocked down receiving a kick while they are on the ground or in the process of falling.

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Why now? The WKF has been progressively tightening safety rules as karate positions itself for continued Olympic inclusion after its debut at Tokyo 2020. A fallen competitor cannot effectively defend against kicks — they lack the base and reaction time. Head and neck trauma from strikes to a compromised position carries significantly higher concussion risk than strikes exchanged while both competitors are standing and prepared.

After tracking legality changes across 30 rule sets, a clear pattern emerges. Techniques get banned when three conditions converge:

1. The defender cannot protect themselves. Kani basami attacks from a blind angle at knee level. Slams at open events catch unprepared competitors. Kicks to fallen opponents target someone who cannot establish a defensive base. The common thread is that the defender has no reasonable opportunity to mitigate the damage.

2. The injury is structural, not superficial. A bruise heals. A broken fibula, a torn ACL, or a cervical fracture may not — at least not fully. Rule committees ban techniques that produce injuries affecting joint stability, spinal integrity, or neurological function. These are injuries that compromise not just the next tournament but the athlete's quality of life for decades.

3. A high-profile incident forces the decision. Yamashita's broken leg in 1980. Repeated slam injuries at ADCC opens. The WKF's Olympic safety scrutiny. Rule changes almost never happen proactively. They happen reactively, after the cost of the current rules becomes undeniable.

The research is unambiguous: martial arts training provides substantial health benefits. Adolescents who train have significantly higher bone density. Older adults who train improve balance, flexibility, and agility beyond what conventional exercise provides. A systematic review in the Journal of Evidence-Based Medicine found that tai chi and moderate martial arts practice are among the most effective exercise forms for long-term health.

But competitive martial arts — with full-contact sparring, high-intensity training camps, and the pressure to win — carries a different risk profile. The same study that documented martial arts health benefits found that research on judo, karate, and taekwondo focused overwhelmingly on competitive performance rather than long-term health outcomes.

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The athletes most affected by technique bans are not the elite competitors — they have the skills to execute and receive dangerous techniques safely. The bans protect the vast majority: recreational practitioners, masters-age competitors, and beginners who train for health, confidence, and community rather than world titles.

This is the tension at the heart of every rule change: the technique that makes a sport spectacular is often the technique that makes it dangerous. Organizations like ADCC, the IJF, and the WKF are not making the sport worse by restricting techniques. They are deciding what the sport is for — and increasingly, the answer includes the athlete's ability to train into their sixties, seventies, and beyond.

Every technique page in our system includes a Competition Legality section showing its status across all relevant rule sets, with linked PDF sources and expandable history timelines. When rules change, we update the data.

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You can see this in action on the Standard Kani Basami page, where the legality section shows eight rule sets — four banning the technique and four allowing it — each with the specific rulebook, year, and historical timeline.

If you spot an error or know about a rule change we have not captured, every legality section has a "Suggest edit" link. Our goal is to be the most accurate, most current source of competition legality data for every fighting technique in the world.

Browse the full taxonomy at the A-Z techniques index, or explore by class: Takedowns, Submissions, Strikes, Throws.

Which fighting technique is banned in the most competitions? The kani basami (scissor takedown) is banned in at least four major international rule sets — IJF judo, IBJJF Brazilian jiu-jitsu, UWW wrestling, and ADCC submission grappling — making it one of the most widely prohibited techniques in combat sports.

Why was kani basami banned in judo? The IJF banned kani basami in 1980 after the technique caused a fibula fracture to Yasuhiro Yamashita at the All Japan Judo Championships. The scissoring action applies dangerous lateral force to the knee, risking ACL, MCL, and bone injuries. The ban has never been reconsidered.

Are slams illegal in BJJ? Under IBJJF rules, slams are illegal. Under ADCC rules, slams are now banned at Open tournaments (as of 2025) but remain legal at Trials and World Championship events. The legality depends entirely on which rule set governs the competition.

What is the most dangerous legal technique in MMA? Several techniques carry high injury risk while remaining legal under the Unified Rules of MMA, including kani basami (rarely used due to risk), heel hooks, and various slam techniques. The August 2025 revision of the Unified Rules did not restrict any additional techniques.

Why do some martial arts allow techniques that others ban? Different organizations prioritize different values. Sambo allows kani basami because their training methodology emphasizes receiving the technique safely. Judo bans it because the risk to unprepared defenders outweighs the competitive value. These are philosophical differences about what competition should prioritize: maximal technique freedom or maximal athlete safety.

How often do competition rules change? Major rule set revisions typically occur every 1-4 years, often timed to Olympic cycles. Between 2024 and 2026, at least six significant technique legality changes occurred across major combat sports organizations.

Can I check if a specific technique is legal in my competition? Yes. Every technique page on Fight Encyclopedia includes a Competition Legality section showing its status across all tracked rule sets, with links to the official rulebook PDFs. Browse the A-Z index to find any technique, or see all rule sets at our Competition Rules Database.

This article is part of a two-part series. Read Part 2: Techniques That Were Banned — And Then Came Back