| Electromyography (EMG) | Shows denervation patterns with fibrillation potentials and reduced motor unit recruitment |
| Creatine kinase (CK) | May be mildly elevated, particularly in Type 3 |
| Muscle biopsy | Shows grouped atrophy characteristic of denervation (rarely needed with genetic testing available) |
| SMN2 copy number determination | Critical for prognosis and treatment planning |
| Databases | OMIMOrphanetClinicalTrialsPubMed |