The bicep slicer, a.k.a the bicep crusher or the bicep lock, is a compression lock used in MMA and submission fighting.
This technique causes intense pain by pressing the bicep into the humerus (the bone connecting the shoulder to the elbow). It can also damage the tendons and ligaments of the elbow by causing the joint to seperate.
To perform the bicep crusher you would insert your arm or leg between the opponent’s upper and lower arm at the elbow. The bone in the forearm or the shin bone should be placed directly against the bicep for the submission to work properly. The opponent’s arm is then put in a flexed positon thereby creating a fulcrum (point of support on which a lever turns when raising or moving something). Pressure can then be applied to the opponent’s flexed arm and the bicep will be pressed into the fulcrum causing pain and the submission.