Sketcher > Dimensioning Sketcher Geometry > Working with Dimension Tools > Normal Dimensions > Dimensioning Splines > To Dimension Spline Interpolation Points
  
To Dimension Spline Interpolation Points
1. Click Sketch > Normal or right-click in the Sketcher window and choose Dimension from the shortcut menu.
2. Click the spline. The system displays the interpolation points.
3. Click the interpolation point to dimension.
4. Click the geometry to which you want to dimension.
5. Click the middle mouse button to place the dimension.