| Amyotrophic lateral sclerosis |
| Extrinsic neoplasia (metastatic tumors) |
| Hereditary spastic paraplegia |
| Intrinsic neoplasia (tumors of spinal cord parenchyma) |
| Multiple sclerosis |
| Normal pressure hydrocephalus |
| Spinal cord infarction |
| Syringomyelia |
| Vitamin B12 deficiency |