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🦴 Scoliosis Cobb Angle & Progression Risk

UseSpine imaging: standing full-spine films, flexion/extension views, CT/MRI — scoliosis follow-up, adult deform…

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SourceCobb JR. Outline for the study of scoliosis. Instr Course Lect 1948;5:261-275

Runs locally in your browser (no PHI uploaded). For licensed clinicians — not a substitute for clinical judgement.
Stored on this device for revisit reminders

This-shift next steps

After scoring: open the scene pack, peer scores, and the matching pathway. Local reference — no HIS write.

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Methodology · worked example, guidelines & full notes
Clinical takeaway

Standing full-spine PA radiograph.

When to use

Spine imaging: standing full-spine films, flexion/extension views, CT/MRI — scoliosis follow-up, adult deformity, stenosis reporting and surgical planning.

How it works

Cobb angle < 10°: spinal asymmetry, not scoliosis Cobb angle 10–25°: mild — observe; repeat every 4–6 months while growing Cobb angle 25–45°: moderate — brace if still growing (Risser 0–2) Cobb angle ≥ 45°: severe — surgical evaluation (curves > 50° may progress ~1°/yr in adults)

Key points

  • Standing full-spine PA radiograph.
  • Each value is graded against published reference ranges.
  • Measurement technique and positioning change the numbers — compare like with like on follow-up.
  • Part of the YuanDoctor MSK measurement topic.

References

  • Cobb JR. Outline for the study of scoliosis. Instr Course Lect 1948;5:261-275
  • Lonstein JE, Carlson JM. The prediction of curve progression in untreated idiopathic scoliosis during growth. J Bone Joint Surg Am 1984;66:1061-1071
  • Richards BS, et al. SRS standardization criteria for brace studies. Spine 2005;30:2068-2075

Worked calculation

The values below come from this tool's own example placeholders and are computed server-side with the formula shown on this page, so the arithmetic can be checked quickly. It demonstrates how to substitute values only — it is not clinical advice and not a real case.

Risser grade (iliac apophysis)2
Age12 years
Prior Cobb angle (same end vertebrae)22 °
Cobb angle28 °

→Cobb angle28°

  • Cobb angle：28 ° → 25–45°: moderate — brace if still growing (Risser 0–2)
  • Lonstein-Carlson progression factor：(28 − 3×2) / 12 = 1.83; higher means greater risk, ≥ 1.4 suggests high risk
  • Bracing：Meets common SRS bracing criteria (age ≥ 10, Risser 0–2, Cobb 25–40°)
Verification & sources · governance
FAQ

Frequently asked questions

What are the limits and cautions when using Scoliosis Cobb Angle & Progression Risk?
For licensed clinicians and clinical researchers. Interpret results with history, investigations and local protocols; not a diagnosis or prescription, and not a substitute for multidisciplinary decision-making or local guidelines.
Does Scoliosis Cobb Angle & Progression Risk upload patient data? Where is it calculated?
Calculation runs locally in the browser; inputs and results are not uploaded. For licensed clinicians only; interpret with history, investigations and local protocols — not a diagnosis or prescription.
How is Scoliosis Cobb Angle & Progression Risk calculated in practice? Can you show a worked example?
Inputs: Risser grade (iliac apophysis) 2, Age 12 years, Prior Cobb angle (same end vertebrae) 22 °, Cobb angle 28 ° → Result: Cobb angle 28 °（Cobb angle: 28 ° → 25–45°: moderate — brace if still growing (Risser 0–2), Lonstein-Carlson progression factor: (28 − 3×2) / 12 = 1.83; higher means greater risk, ≥ 1.4 suggests high risk, Bracing: Meets common SRS bracing criteria (age ≥ 10, Risser 0–2, Cobb 25–40°)）
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