A drive mechanism for use with an elongated medical implement comprises a motor, a first pulley mechanically coupled to the motor, and a second pulley. The drive mechanism further comprises a connector mechanically coupled to the second pulley. The connector is configured for laterally receiving the medical implement. The drive mechanism further comprises a belt wrapped around the first and second pulleys to transmit force from the motor to the connector. A robotic medical system comprises a user interface configured for receiving at least one command, a drive mechanism including a motor and a connector configured for laterally receiving the medical implement, and an electrical controller configured for directing the motor to cause the drive mechanism to move the medical implement within at least one degree-of-freedom.