The screw 2220 rotated as indicated by the arrows in FIG. 222A. The rotation advances the screw through the wall as shown in FIG. 222B. Once through the wall, a pin 2225 or other devices inserted into the middle of or a lumen running through the screw to cause the split portion 2221 to open out as shown in FIG. 222C and provide larger access into the adjacent space.