Other degenerative diseases of basal ganglia (G23) ICD-10-CM
The G23 code range covers other degenerative diseases of basal ganglia with 7 ICD-10-CM diagnosis codes. 6 of them are billable and valid for claim submission in fiscal year 2027, and the category headers group them but cannot themselves be billed.
Type 2 Excludes
A type 2 excludes note represents "Not included here". An excludes2 note indicates that the condition excluded is not part of the condition represented by the code, but a patient may have both conditions at the same time. When an Excludes2 note appears under a code, it is acceptable to use both the code and the excluded code together, when appropriate.
- multi-system degeneration of the autonomic nervous system G90.3
Codes in the G23 Range 7 codes · 6 billable
- G23 Other degenerative diseases of basal gangliaNon-billable
- G23.0 Hallervorden-Spatz disease
- G23.1 Progressive supranuclear ophthalmoplegia [Steele-Richardson-Olszewski]
- G23.2 Striatonigral degeneration
- G23.3 Hypomyelination with atrophy of the basal ganglia and cerebellum
- G23.8 Other specified degenerative diseases of basal ganglia
- G23.9 Degenerative disease of basal ganglia, unspecified
Clinical Terms in This Code Range
Definitions from the National Library of Medicine for conditions coded in the G23 range.
Pantothenate Kinase-Associated Neurodegeneration
A rare autosomal recessive degenerative disorder which usually presents in late childhood or adolescence. Clinical manifestations include progressive MUSCLE SPASTICITY; hyperreflexia; MUSCLE RIGIDITY; DYSTONIA; DYSARTHRIA; and intellectual deterioration which progresses to severe dementia over several years. (From Adams et al., Principles of Neurology, 6th ed, p972; Davis & Robertson, Textbook of Neuropathology, 2nd ed, pp972-929)
Striatonigral Degeneration
A sporadic neurodegenerative disease with onset in middle-age characterized clinically by Parkinsonian features (e.g., MUSCLE RIGIDITY; HYPOKINESIA; stooped posture) and HYPOTENSION. This condition is considered a clinical variant of MULTIPLE SYSTEM ATROPHY. Pathologic features include a prominent loss of neurons in the zona compacta of the SUBSTANTIA NIGRA and PUTAMEN. (From Adams et al., Principles of Neurology, 6th ed, p1075-6)
About the G23 Code Range
These nervous system conditions involve degeneration of the basal ganglia and fall within the movement disorders block.
G23 separates specific conditions from other specified and unspecified degenerative diseases of the basal ganglia. G23.0 and G23.1 identify named diseases. G23.2 identifies striatonigral degeneration, while G23.3 names a condition involving both the basal ganglia and cerebellum. G23.8 is for other specified diseases, and G23.9 is for an unspecified disease.
Questions About This Page
How many billable codes are in the G23 range?
Of the 7 codes in this range, 6 are billable and valid for claim submission from October 1, 2026 through September 30, 2027. Category header codes group them but cannot be reported on claims.
What does the G23 range classify?
The range classifies other degenerative diseases of basal ganglia. Each code links to its own reference page with billing status, MS-DRG grouping, coding notes, and clinical information.
Related References
Source: CMS FY 2027 ICD-10-CM Tabular List and order file, effective October 1, 2026 through September 30, 2027.
