| Description | Grade |
| Signs and symptoms of root involvement but no cord disease. | 0 |
| Signs of cord disease. Normal gait. | 1 |
| Mild gait abnormality. Able to be employed. | 2 |
| Gait abnormality prevents employment. | 3 |
| Able to walk only with help. | 4 |
| Chair bound or bed ridden. | 5 |