Bone anchors useful in rotator cuff repair optimize the thread pattern for engaging different types of bone tissues, including harder cortical bone and softer cancellous bone. Bone anchors may include fine threads for engaging cortical bone and coarse threads for engaging cancellous bone. Threads can be made finer by increasing root diameter and surface angle of the threads. The pitches of the fine and coarse threads are kept the same, which allows fine threads to follow the impression created by coarse threads as the anchor is driven into a bone. Threads that engage cortical bone can be multi-fluted and include a first flute that follows the same thread pattern as coarse threads such that first flute follows the groove created by the coarse threads as the bone anchor is driven into a bone. Bone anchors can have a distal non-threaded stabilizing extension at the distal end.