Instruments and methods for reducing and stabilizing bone fractures are presented, which include providing a cavity in bone, such as a vertebra, wherein the cavity is proximate to an endplate of the bone, such as a vertebra endplate, and wherein the cavity extends radially from a passage into the cavity. The top block provides an aesthetically pleasing front surface the upper edge of which may be rectilinear or contoured to fit various applications and appearance requirements. An alternating control signal input from a control circuit controls the control and sync FETs to be switched on alternately. The local contact list is generated by selecting, for inclusion in the local contact list, one or more contacts that are not in the contact list that is stored for the user and are within a second predetermined geographic location. After using the resource, any non-priority thread releases the resource lock to the priority thread if the priority thread has requested the resource, without regard to whether any other threads may be waiting for the resource.