One of the less well known but almost iconic of ninja tools are hand claws or shuko. These concealed tools were also versatile weapons and their use was only limited by the imagination of the ninja. There was two principle designs; one with claws on the inner palm side and one with claws projecting over the knuckles in a ‘wolverine’ style. The later are purely for fighting and their adaptability and concealment is questionable. We will be looking at the former which has many more uses and can be concealed during combat. This design of shuko is unique to Togakure Ryu Ninjutsu.
The word shuko is made of two kanji 手鉤. The first ‘shu’ 手 means hand, and the second ‘kou’ 鉤 means hook or barb. These shuko, coming from Togakure Ryu, are one of the Sanpo Hiden (three secrets) of that school along with senban shuriken and shinodake (a multiple application bamboo tube). When climbing the shuko were often used in conjunction with a set of metal claws on the feet called sokkou or ashiko 足鉤. The two kanji for this are ‘soku’ 足 meaning foot or leg (and can be read as ashi), and ‘kou’ 鉤 again meaning hook or claw.
At the time of their use the landscape and habitat of Japan was predominantly rural, and techniques and tools reflected this. The shuko were principally a climbing aid for large trees, and despite the Hollywood portrayal, their use on stone walls was minimal. The types of tree were also a factor. They work well on trees that have thick ridged bark, while trees with thinner bark offer less purchase for the claws to anchor on to. In conjunction with the sokkou these tools would enable the ninja to ascend large trees to a suitable height for observation, ambush or sniping with bows or blowpipes. Also larger trees with thick boles were likely to support the ninja at greater heights, which is why these tools were needed. The climb would require all limbs thereby leaving nothing free to hold swords or other ninja weapons. The answer would be to tie equipment together in a bundle and attach a long rope to pull it up once at the required height. This also meant if the ninja slipped he was unencumbered and could roll away from any impact on the ground. As the ground was un-paved dirt the sokkou wouldn’t impede landing safely or rolling. The ability to perform no-handed rolls on a hard surface however, really comes into its own in these circumstances!
While tree climbing is the better known use of shuko they could also used for climbing thatch roofs, anchoring into wooden beams and some limited use on cliff faces. They are often portrayed used on stony castle walls, but shuko allow little purchase as the iron hooks are curved and won’t catch into crevices between fitted stone. In these circumstances a kaginawa (rope and grapnel) and kunai would be more likely to be employed - the effect of getting it wrong could be quite a let-down.
In combat the use of the shuko is from a position of concealment, and the stances reflect this. While they are very similar to the unarmed stances of the same name (within the Bujinkan) they are adapted to take into account the characteristics of the weapon. The hands are positioned to ensure the protruding claws are not held against the limbs or body of the ninja and each technique allows for this also (the idea being to perforate your opponent not yourself!).
When punching while wearing shuko, the fist used is shikan ken as this allows for the weapons shape. A ‘normal’ fist or fudoken would be impractical. Strikes with the shuko themselves are usually delivered using the metal band that encircles the palm, using the edge of the hand. The claws are used to capture the fist, dig into limbs and torso, rake vulnerable areas like the face or groin, or used to hook into armour to allow purchase for throws. One thing to note is that the claws are usually round spikes so as to allow purchase when dug into trees and don’t have a cutting edge as such. This means in combat they will anchor into the skin and underlying tissue rather than cut. When torn out they leave ragged cuts and tears in the skin which are then prone to infection. Some of the less than savoury practices in this time of dirty hand-to-hand fighting would be to smear the hooks with excrement to cause terminal infections such as gangrene. This secondary disablement of the opponent may well have been beneficial to the long term goals of the ninja, where the incapacitating of numbers of enemy would serve to slow down a larger body of men as they cared for the injured. It’s worth bearing in mind that some of the missions of the ninja were aimed at a larger tactical objective than a one-person target.
While fighting with shuko against an unarmed opponent made life easy for the ninja, once weapons were introduced things got a bit more interesting! Against an opponent wielding a sword the shuko were used to take control of the blade and / or limbs, and disarm the opponent. One of the more well known techniques for this is to intercept a downward cut early with one shuko, clasp the second on the back of the blade and twist the two together thus locking the blade in the spikes. The opponent would then be disarmed with kicks and taijutsu. It was also used against long weapons, hooking into wooden shafts of spears and staves alike. A high level of understanding of weapons, timing and distance is needed for this. Some techniques employ the use of the sokkou as well, kicking in a raking motion to tear skin or stamping into the chest to perforate the opponent.
The Togakure Ryu Shuko are unique to the ninja and are a versatile way to claw your way out of a situation.