| G1225 | Progressive spinal muscle atrophy |
| G1229 | Other motor neuron disease |
| G128 | Other spinal muscular atrophies and related syndromes |
| G129 | Spinal muscular atrophy, unspecified |
| G13 | Systemic atrophies primarily affecting central nervous system in diseases classified elsewhere |
| G130 | Paraneoplastic neuromyopathy and neuropathy |
| G131 | Other systemic atrophy primarily affecting central nervous system in neoplastic disease |
| G132 | Systemic atrophy primarily affecting the central nervous system in myxedema |
| G138 | Systemic atrophy primarily affecting central nervous system in other diseases classified elsewhere |
| G14 | Postpolio syndrome |
| G20 | Parkinson's disease |
| G20A | Parkinson's disease without dyskinesia |
| G20A1 | Parkinson's disease without dyskinesia, without mention of fluctuations |
| G20A2 | Parkinson's disease without dyskinesia, with fluctuations |
| G20B | Parkinson's disease with dyskinesia |
| G20B1 | Parkinson's dis with dyskinesia, w/o mention of fluctuations Parkinson's disease with dyskinesia, without mention of fluctuations |
| G20B2 | Parkinson's disease with dyskinesia, with fluctuations |
| G20C | Parkinsonism, unspecified |
| G21 | Secondary parkinsonism |
| G210 | Malignant neuroleptic syndrome |
| G211 | Other drug-induced secondary parkinsonism |
| G2111 | Neuroleptic induced parkinsonism |
| G2119 | Other drug induced secondary parkinsonism |
| G212 | Secondary parkinsonism due to other external agents |
| G213 | Postencephalitic parkinsonism |
| G214 | Vascular parkinsonism |
| G218 | Other secondary parkinsonism |
| G219 | Secondary parkinsonism, unspecified |
| G23 | Other degenerative diseases of basal ganglia |
| G230 | Hallervorden-Spatz disease |
| G231 | Progressive supranuclear ophthalmoplegia [Steele-Richardson-Olszewski] |
| G232 | Striatonigral degeneration |
| G233 | Hypomyelination with atrophy of basal ganglia and cerebellum Hypomyelination with atrophy of the basal ganglia and cerebellum |
| G238 | Other specified degenerative diseases of basal ganglia |
| G239 | Degenerative disease of basal ganglia, unspecified |
| G24 | Dystonia |
| G240 | Drug induced dystonia |
| G2401 | Drug induced subacute dyskinesia |
| G2402 | Drug induced acute dystonia |
| G2409 | Other drug induced dystonia |
| G241 | Genetic torsion dystonia |
| G242 | Idiopathic nonfamilial dystonia |
| G243 | Spasmodic torticollis |
| G244 | Idiopathic orofacial dystonia |
| G245 | Blepharospasm |
| G248 | Other dystonia |
| G249 | Dystonia, unspecified |
| G25 | Other extrapyramidal and movement disorders |
| G250 | Essential tremor |
| G251 | Drug-induced tremor |