ICD-10 Code G23.8 – Other specified degenerative diseases of basal ganglia (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code G23.8 – Other specified degenerative diseases of basal ganglia
What it is
G23.8 identifies a degenerative disorder affecting the basal ganglia that does not fit a more specific ICD-10 category. Use it when the record clearly documents another specified basal ganglia degeneration.
Clinical signs
Clinical features vary; refer to documentation. Basal ganglia disorders commonly involve movement abnormalities such as rigidity, bradykinesia, dystonia, tremor, or gait changes, but the exact pattern depends on the underlying condition.
When to use this code
Use this code when the clinician documents a specified degenerative disease of the basal ganglia and no more precise code is available. It may be appropriate for a named disorder or a documented degenerative syndrome involving the basal ganglia. Check documentation if the diagnosis is uncertain or incomplete.
Do not use for
Do not use G23.8 for Parkinson’s disease, progressive supranuclear palsy, or other separately coded movement disorders. If the chart only says “basal ganglia disease” without a degenerative diagnosis, check documentation.
Coding tip
Code G23.8 only when the provider specifies a degenerative basal ganglia disorder and no more specific ICD-10 code applies.