Definition
De novo curve in a skeletally mature spine from asymmetric disc and facet degeneration, with a coronal Cobb angle over 10 degrees.
Epidemiology
- Prevalence rises with age
- Curve is usually in the lumbar or thoracolumbar spine
Classification
SRS-Schwab adult spinal deformity classification
| Component | Categories |
|---|---|
| Coronal curve type | T thoracic only, L thoracolumbar or lumbar only, D double, N no major coronal deformity |
| Pelvic incidence minus lumbar lordosis | Under 10, 10 to 20, over 20 degrees |
| Sagittal vertical axis | Under 40, 40 to 95, over 95 mm |
| Pelvic tilt | Under 20, 20 to 30, over 30 degrees |
Clinical Features
- Mechanical back pain
- Neurogenic claudication and radiculopathy, often on the concave side of the curve
- Sagittal imbalance with standing fatigue and a forward lean
Investigations
- Standing full length posteroanterior and lateral radiographs including the pelvis and hips
- Measure Cobb angle, sagittal vertical axis, pelvic incidence, lumbar lordosis and pelvic tilt
- MRI or CT myelogram for stenosis, and DEXA
Management
- Nonoperative care. Physiotherapy, core strengthening, analgesia and targeted injections
- Decompression alone. Focal stenosis in a stable curve without sagittal imbalance. Risk of curve progression
- Short segment fusion. Decompression with fusion of the symptomatic levels
- Long fusion with osteotomy. For sagittal imbalance, often extended to the pelvis
Complications
- Pseudarthrosis
- Proximal junctional kyphosis
- Adjacent segment degeneration
- Infection and neurological injury
References
Schwab F, Ungar B, Blondel B, Buchowski J, Coe J, Deinlein D, DeWald C, Mehdian H, Shaffrey C, Tribus C, Lafage V. Scoliosis Research Society-Schwab adult spinal deformity classification: a validation study. Spine (Phila Pa 1976). 2012, 37(12), 1077-82. PubMed
Reviewed by Professor Phong Tran, Head of Orthopaedic Surgery, Western Health. Last updated 21 October 2026.