Kansetsu Waza Assistance Request

I only need a small piece of information to complete my book which facilitates the understanding and study of all fighting/self defence methods. I'm using this blog to request any reader's assistance in this regard.

I'm writing a chapter on joint-locking techniques (kansetsu waza), focusing on techniques applied to the upper limb because of their popular and tactical use. Incredible as it may seem given the popularity of these techniques, to the best of my knowledge there is no anatomical description of these techniques in the martial arts and related literature.

The medical literature is of no help because the vast majority of injuries that occur in the upper limb are as a result of a fall on an outstretched hand (FOOSH injuries). The forces experienced when falling on an outstretched hand are different to those applied with a joint locking technique. For instance, a fall on an outstretched hand involves an extended hand whereas most joint-locking techniques involve a flexed hand.

I've described the anatomical effect of techniques that target the shoulder based on the movement of the humerus in the shoulder joint. This produced a classification that can be used to understand and study familiar and unfamiliar techniques that target the shoulder joint.

I've described the possible dislocations (3) that techniques targeting the elbow might produce.

There is a technique that targets the forearm taught in aikido and some jujutsu systems. This technique is called kote hineri (forearm twist; see right) in Jan de Jong jujutsu and involves applying forces to the hand to rotate the forearm towards the body. I thought obtaining an anatomical description of the effects of this technique would prove the most difficult to obtain, but it turned out to be the easiest. A researcher was interested in the effects of hyper-pronation of the forearm and published the results of a study in 1949. He used 18 cadavers and stripped the forearm of the tissues andheld the shaft of the humerus firmly in a vice and the forearm was gripped in a wooden clamp just above the wrist and slowly pronated.

I'm interested in three basic wrist locks. The first is the popular wrist crush (see right), also known as 'goose-neck' wrist lock, and gokyo (fifth teaching) in aikido. A study was conducted on this technique and published in an academic journal so I have some information on the possible anatomical effects of this technique. However, it has to be said the study was a little light on.

The second wrist lock is what De Jong referred to as yoko tekubi hishigi (side wrist lock; see right and down), which aikido refers to as nikyo (second teaching). A study on the possible anatomical effects of this technique was published in an academic journal by the above author of the study on gokyo and another by another author. Again, these studies are not as comprehensive as they might be.

The third wrist lock is the ubiquitous wrist twist (see below right). I have no information on the anatomical effects of this technique other than a general possible explanation provided by a physiotherapist. While I would appreciate information on the above two wrist locks, it is a description of the anatomical effects of the wrist twist that I am missing. If any reader could assist with a description from an authoritative source (anatomist, biomechanist, etc), I would be very appreciative. You would be contributing to the general body of knowledge because no such description appears to exist today.

Thank you.