Posture & Spine

Cobb Angle Measurement

Measuring scoliosis curvature angle on X-ray images.

Cobb Angle Measurement uses AI to find the vertebral landmarks automatically once a standing spine X-ray is uploaded, and calculates the Cobb angles of the curves by itself. There is no need to place lines or points; if needed, the points can be dragged to correct them.

What Is It Used For?

Recording curve magnitude numerically during scoliosis follow-up
Comparing radiographs taken on different dates
Monitoring the course of the curve during exercise or bracing
Providing a shared value for communication between physician and physiotherapist

Measured Parameters

Cobb angle (degrees)
Position of the vertebrae from T1 to L5 (automatic detection)
Upper and lower end vertebrae (the most tilted vertebrae)
Superior endplate of the upper end vertebra and inferior endplate of the lower end vertebra
Apical vertebra (the apex of the curve)
A separate angle for each curve when more than one is present

Setup and Camera Placement

This measurement is made on an existing X-ray image, not with the camera.
Use a standing anteroposterior (AP/PA) radiograph showing the whole spine.
Upload the digital image file where possible; if photographing a screen, shoot straight on, without tilt or glare.

Tips for Accurate Measurement

Review the automatically detected points before saving; zoom in if a correction is needed.
At follow-up, check that the automatically selected end vertebrae match the levels of the previous measurement.
Avoid low-resolution, cropped or skewed images.
Automatic detection may struggle with poor image quality; check the points manually in such cases.

How Is the Test Done?

Select the client and upload the X-ray image.
AI finds the vertebral landmarks automatically; end vertebrae and Cobb angles are calculated within seconds.
Review the result. If needed, drag the points to correct them; the angles update instantly.
Save the measurement with the vertebral levels to the client profile.

What Will I See on the Results Screen?

Automatically marked vertebral points and reference lines on the X-ray
The Cobb angle in degrees
A dated record in the client profile and comparison with earlier measurements

Interpreting the Results

In the literature, angles of 10° or more are a commonly used threshold in the definition of scoliosis; however, diagnosis is made only by a physician, together with clinical and radiological findings.
A difference of a few degrees (around 3–5°) between Cobb measurements is expected variability; changes of this size should not be read as progression on their own.
A higher angle reflects a more pronounced curve; monitoring and treatment decisions belong to the physician.
Radiographs taken in different positions (lying/standing) should not be compared directly.

Clinical Use Example

For a client diagnosed by a physician with adolescent idiopathic scoliosis and referred to a scoliosis-specific exercise programme, the Cobb angle is measured for follow-up purposes on the control radiographs requested by the physician. Values are stored chronologically in the profile and added to the report shared with the physician. This measurement does not replace the radiology report; assessment and treatment decisions belong to the physician.