There is provided a device to promote healing of cut tissue members, such as nerves, tendon or muscles, within a body. The device is of hollow construction and comprises apertures into which the cut ends of the tissue members are placed and fixed, usually by a fibrin-based tissue glue. Located between the apertures is a substance to promote healing of the tissue member such as, for example, nerve growth factor. Optionally the device may be used in conjunction with the external reservoir of the substance and/or with a time-operated pump to deliver the substance to the device. The device is biodegradable and is preferably composed of watersoluble glass.