Ara-Waza and Henka-Waza
Ara-waza, literally coarse techniques, are occasionally practiced by Iwama style Aikido practitioners. These techniques are intended to explicitly show the more vicious applications hidden in Aikido technique and include simple kicks targeting the knees and entangling or twisting joints during throws with the intent to break them. Some henka-waza (modified basic techniques) in Iwama style Aikido also include entangling joints, locking large joints, strikes to vital points, and occasionally chokes using the arm or the partner's dogi. As Aikido practitioners are usually not skilled in choking techniques these are never performed fully for safety reasons.
Read more about this topic: Iwama Style