A sterile device intended to be inserted into a bone tunnel during an arthroscopic procedure to reduce the loss of the irrigation fluid used to maintain visualization, while allowing the passage of instruments (e.g., probes, guide pins, shavers and graspers) through its lumen to access the joint. It is a short, rigid, cannulated tube which tapers distally with a penetrable seal on the proximal end. It is inserted manually into the bone tunnel, or may be supplied with dedicated instruments for insertion (e.g., obturator). The device is available in a variety of diameters, and is typically made of plastic. This is a single-use device.