Making Slanted Dimension Extension Lines
To slant dimension extension lines:
When you insert or select a dimension, handles 
appear so you can drag the dimension to slant the extension lines. Drag a handle at the end of the extension line nearest the arrow (the pointer changes to 
when it is over a handle that effects the slant).
To return the dimension to its original position, right-click the dimension and select . You can also drag the handle until the dimension snaps back to its original position.