The Cobb Angle 
graphics tool is used for measuring the curvature of the spine; the tool supports consecutive Cobb angles.
1. Click Cobb Angle .
2. Select two points on the image for the first line of the Cobb angle.
3. Select the next two points for the second line that will complete the first Cobb angle. If only a single Cobb angle measurement is needed, end the measurement.
4. Select the next two points for the line that will complete the next consecutive Cobb angle. The two points ending the previous Cobb angle also represent the first two points for this Cobb angle. If this is the final consecutive Cobb angle, end the measurement.
5. Repeat step 4 for additional consecutive Cobb angles measurements.