A device for treating a fistula is disclosed. In one aspect of the invention the device comprises a probe 2 and a seton 1 connectable together end-to-end. This make the seton 1 easier to insert by stopping the seton 1 abrading or ripping surrounding tissue as the seton 1 is pulled through the fistula. The seton 1 may be connected to the probe 2 by a screw attachment 26, In another aspect the seton 1 comprises a pharmaceutical agent and/or biodegradable material. In a further aspect the device comprises a seton 1 and an attachment device 8, the seton 1 being formed with a first end and a second end that are securable to each other by the attachment device 8.
