Cancellous screw

Cancellous screws consist of a thicker inner diameter with thinner threads that provide more purchase in cancellous bone, usually in the metaphyseal area. This is Self Tapping Screw. Self Tapping Screws cuts its own thread while being driven into the bone. It makes a small hole while entering the bone which creates a tight friction fit between the threads. This helps fight vibration loosening and allows the parts to be taken apart if needed. Cancellous thread profile uses deep cutting threads with a large pitch to increase resistance to pullout. The large pitch also accelerates screw insertion and removal.