Is G11.9 a billable ICD-10-CM code?

Yes. G11.9 is a billable, specific ICD-10-CM code and is valid for submission on a claim.

Where does G11.9 sit in the tabular list?

Diseases of the nervous system (G00-G99), in the block Systemic atrophies primarily affecting the central nervous system (G10-G14).

G11.9

G11.9 — Hereditary ataxia, unspecified

Billable / specific codeICD-10-CM

G11.9 is a billable, specific ICD-10-CM code for hereditary ataxia, unspecified. It is valid for submission on a claim.

Inclusion terms

Alternative wordings a physician may use in the chart for this same code.

Hereditary cerebellar ataxia NOS
Hereditary cerebellar degeneration
Hereditary cerebellar disease
Hereditary cerebellar syndrome

Risk adjustment

G11.9 risk-adjusts. Under the CMS-HCC V28 model it maps to this category:

HCC 200 Friedreich and Other Hereditary Ataxias; Huntington Disease0.279 RAF

Coefficient shown for the Community Non-dual Aged segment. A higher HCC in the same hierarchy will suppress this one, so capturing it does not always add score.

Medicare coverage

G11.9 is named in 8 Medicare coverage policies — 8 listing it as supporting medical necessity. Which of them applies to you depends on your Medicare contractor, and coverage genuinely differs by state.

A53064Billing and Coding: Outpatient Occupational Therapy
A53065Billing and Coding: Outpatient Physical Therapy
A54969Billing and Coding: Nerve Conduction Studies and Electromyography
A56612Billing and Coding: CT of the Head

How G11.9 is indexed

Coders do not find codes by browsing the tabular list — they look them up in the alphabetic index, under the word the physician wrote. These are the index entries that lead here, so you can see which chart wordings map to G11.9.

Ataxia, ataxy, ataxic›brain(hereditary)
Ataxia, ataxy, ataxic›cerebellar(hereditary)
Ataxia, ataxy, ataxic›cerebral(hereditary)
Ataxia, ataxy, ataxic›hereditary
Disease, diseased›spinocerebellar(hereditary)
Paralysis, paralytic›ataxic(hereditary)
Degeneration, degenerative›cerebellar NOS›primary(hereditary) (sporadic)
Sclerosis, sclerotic›hereditary›cerebellar
Syndrome›cerebellar›hereditary

Related codes at this level

Codes that share G11. If G11.9 is not quite right, the correct code is usually one of these.

Questions about G11.9

Is G11.9 a billable ICD-10-CM code?: Yes. G11.9 is a billable, specific ICD-10-CM code and is valid for submission on a claim.
Where does G11.9 sit in the tabular list?: Diseases of the nervous system (G00-G99), in the block Systemic atrophies primarily affecting the central nervous system (G10-G14).