Joint Locks (Kansetsu-waza)

Kansetsu-waza are the judo joint locks, the submissions that stretch or twist a joint, and the Kodokan lists ten: nine on the elbow and one on the knee. Judoinfo.com lists kansetsu waza as "joint locking techniques".

Japanese name: kansetsu-waza, "joint locking techniques".
Kodokan classification: one of the three groups of katame-waza, with osaekomi-waza and shime-waza.
In BJJ: BJJ Heroes gives the armbar's Japanese name as ude hishigi juji gatame and the kimura's as gyaku ude-garami, the lock Masahiko Kimura used to beat Helio Gracie.

What are the 10 Kodokan joint locks?

The Kodokan list of techniques names: Ude-garami, Ude-hishigi-juji-gatame, Ude-hishigi-ude-gatame, Ude-hishigi-hiza-gatame, Ude-hishigi-waki-gatame, Ude-hishigi-hara-gatame, Ude-hishigi-ashi-gatame, Ude-hishigi-te-gatame, Ude-hishigi-sankaku-gatame, Ashi-garami.

Ude-garami is the twisting lock: the Kodokan defines it as twisting and locking the elbow joint by grabbing the wrist, which covers both the kimura and the americana. The ude-hishigi family stretches the elbow, and each name says what does the stretching: juji-gatame with the hips and legs across the body, ude-gatame with both hands, hiza-gatame with the knee, waki-gatame with the armpit, hara-gatame with the belly, ashi-gatame with the leg, te-gatame with the hand, sankaku-gatame from a triangle. Ashi-garami is the odd one out, defined as stretching and locking the opponent's knee joint.

Which joint locks are legal in judo and BJJ?

In a judo contest the IJF Sport and Organisation Rules allow joint locks on the elbow only. A lock on any other joint, including ashi-garami, the one Kodokan lock on the knee, is hansoku-make, and so is a shoulder lock done as a variation of te-gatame.

BJJ opens the joints by age and belt. The IBJJF Rules Book's table of illegal moves gives:

Armbar, kimura and americana: not on the table.
Straight ankle lock, omoplata: from age 16.
Wrist lock: from adult blue belt.
Kneebar, toe hold, bicep and calf slicers: from adult brown belt.
Heel hook and other knee-twisting locks: adult brown and black belts in no-gi only.

How do you train joint locks safely?

Isolate the joint before you extend it. In juji-gatame the elbow must be above your hips and the thumb pointing up before any pressure goes on.
Apply slowly, in one direction. Joint locks are finished by a small, steady movement of the hips, never a jerk.
Tap early when caught. The elbow gives little warning.
Release the instant your partner taps.
Drill the control positions, the pin before the lock, more than the finish. A lock from a loose position fails or injures.

The most common mistake is pulling the arm with the hands. The hands hold the wrist; the hips do the stretching. If your arms are tired after an armbar, the mechanics were wrong.

Armlock drilling is hard on elbows and fingers. Our BJJ training gear is rash guards and spats for rounds with and without the gi.

For a full book on these techniques, see Vital Judo: Grappling Techniques by Isao Okano, one of our picks in the best judo books for BJJ players.