- Displaying Inflection Points
The Show Inflection Points tool displays all points where the concavity of a spline changes.
- Displaying the Minimum Radius of a Spline
The Show Minimum Radius 
tool (Spline Tools toolbar) displays the radial measurement of the curve with the smallest radius of a spline.
- Setting a Fixed Length
You can set a dimension to fix the length of a spline. You can reference this dimension in custom properties, configurations, equations, and tables, including design tables and BOMs.
- Tangent to Face Relations with Splines
Add Tangent Face 
or Equal Curvature 
relations between adjacent faces and 2D or 3D splines.
- Curvature Combs
Curvature combs provide visual enhancement of the slope and curvature of most sketch entities in part, assembly, and drawing documents.
- Converting Spline Types
You can convert splines to style splines and vice versa. This is helpful when you want to sketch a spline by its through points, but then convert it to a style spline.