A rooter includes a rotatable element, an actuator for causing the rotatable element to rotate, and a coupling feature for rotatably coupling an elongate medical instrument to the rotatable element. The rotatable element may be at least partially contained within the interior of a housing or another element that remains substantially stationary as the actuator causes the rotatable element to rotate. The rooter may be used with a variety of elongate medical instruments, such as needles, drill bits, trocars, wires, catheters, tubes, and other elongate instruments that are used to enable or effect medical procedures within the body of a subject. The rooter may be used for a variety of purposes, including, without limitation, the introduction of an elongate medical instrument into the body of a subject or its removal from the subject's body; removing, breaking up, or eliminating obstructions (e.g., blood clots, plaques, etc.) from the body of a subject; and obtaining samples from a subject's body.