Almost every scoliosis appointment involves a discussion of “degrees” and “Cobb angle.” Understanding what this number means and what it doesn’t, helps families interpret x-rays and treatment decisions with more confidence.
The Cobb angle is the standard way of measuring the size of a scoliosis curve. On an x-ray, clinicians identify the most tilted vertebra at the top and bottom of the curve and draw lines along their endplates. The angle where these lines intersect is the Cobb angle.
While exact cut-offs vary slightly, Cobb angles are often grouped as:
These bands help guide monitoring and treatment recommendations.
It’s important to remember that x-ray measurements have a small margin of error, often around 3–5 degrees. A change from 18° to 20° may not be clinically meaningful, whereas a change from 18° to 28° certainly is. At Dorsi, we always interpret numbers in context.
The same Cobb angle can mean different things at different ages:
That’s why we pair Cobb angle with growth status and curve pattern when planning care. We utilise a special calculation to assess progression risk.
Dorsi Spinal Institute uses repeat imaging at safe intervals to track Cobb angle over time. We look for:
Change, not just a single number, often drives decisions.
We believe numbers should never be a mystery. At Dorsi, clinicians sit down with families to show x-rays, explain Cobb measurements, and discuss what the current angle means practically, today and in the future.
If you’ve been told a Cobb angle but don’t fully understand its implications, bring your imaging to Dorsi Spinal Institute. We’ll translate technical details into clear, usable information and a tailored plan.
Related reading: see our blogs on official diagnosis, understanding your child’s diagnosis, and curve correction outcomes.
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