Hart-International Spine Study Group proximal junctional kyphosis severity scale.
| Characteristic | Points |
| Neurological deficit | |
| None | 0 |
| Radicular pain | 2 |
| Myelopathy/motor deficit | 4 |
| Focal pain | |
| None | 0 |
| VAS ≤4 | 1 |
| VAS ≥5 | 3 |
| Instrumentation problem | |
| None | 0 |
| Partial fixation loss | 1 |
| Prominence | 1 |
| Complete fixation loss | 2 |
| Change in kyphosis/PLC integrity | |
| 0° to 10° | 0 |
| 10° to 20° | 1 |
| >20° | 2 |
| PLC failure | 2 |
| Upper instrumented vertebra/adjacent vertebra fracture | |
| None | 0 |
| Compression | 1 |
| Burst/chance fracture | 2 |
| Translation | 3 |
| Level of upper instrumented vertebra | |
| Thoracolumbar junction | 0 |
| Upper thoracic spine | 1 |
Abbreviation: PLC, posterior ligamentous complex.