ICD-10 G04.1
Billable / Specific HCC v28: 72 CCTropical spastic paraplegia
About ICD-10-CM G04.1
ICD-10-CM code G04.1 represents Tropical spastic paraplegia. This is a billable/specific code in the Nervous System chapter (block G04). The 2026 edition of ICD-10-CM G04.1 became effective on October 1, 2025.
Coding Tips for G04.1
Specialist guidance from the PayerReady Medical Coding Team. Specificity warnings, HCC capture rules, sequencing notes.
G04.1 is a CMS-HCC v28 risk-adjustment code (category 72). To count for the patient Risk Adjustment Factor (RAF), document the diagnosis with MEAT language each calendar year: Monitored, Evaluated, Assessed, Treated. A diagnosis on the problem list alone does not satisfy CMS RADV audit standards. Include the diagnosis in the assessment with current status and current treatment plan.
G04.1 is designated CC for MS-DRG grouping. On inpatient claims, this code can shift the DRG to the with-CC variant when documented as a present-on-admission secondary diagnosis. Hospital CDI programs flag CC opportunities during chart review. Failure to capture this code may leave 30 to 80 percent of the inpatient stay revenue unrealized.
Medicare Advantage HCC Impact
Capture this diagnosis annually for accurate risk adjustment. Missed HCC captures are the #1 revenue leak in Medicare Advantage risk programs.
Inpatient DRG Impact, CC
codes Tropical spastic paraplegia. As a Complication/Comorbidity (CC), this contributes to DRG severity adjustment when documented alongside the principal diagnosis.
Medicare LCD Coverage for G04.1
Local Coverage Determinations (LCDs) from CMS MACs that list G04.1 as a covered diagnosis.
Showing top 10 of 806 total . Click a CPT for full coverage scope.
Commercial Payer Coverage
Coverage policies from major commercial payers referencing G04.1.
1 Cigna
5 Medicare
CPT Codes Commonly Billed with G04.1
Procedures frequently paired with this diagnosis based on PayerReady's Dx↔Px linkage data.
- 29405 CMS LCD: Billing and Coding: Outpatient Physical Therapy CMS LCD
- 95992 CMS LCD: Billing and Coding: Outpatient Physical Therapy CMS LCD
- 29280 CMS LCD: Billing and Coding: Outpatient Physical Therapy CMS LCD
- 97010 CMS LCD: Billing and Coding: Outpatient Physical Therapy CMS LCD
- 29515 CMS LCD: Billing and Coding: Outpatient Physical Therapy CMS LCD
- 97550 CMS LCD: Billing and Coding: Outpatient Physical Therapy CMS LCD
- 97116 CMS LCD: Billing and Coding: Outpatient Physical Therapy CMS LCD
- 97546 CMS LCD: Billing and Coding: Outpatient Physical Therapy CMS LCD
- 29445 CMS LCD: Billing and Coding: Outpatient Physical Therapy CMS LCD
- 29075 CMS LCD: Billing and Coding: Outpatient Physical Therapy CMS LCD
Convert G04.1 to ICD-9-CM
Per CMS General Equivalence Mappings (GEMs), useful for legacy data review and historical claim analysis.
| ICD-10 | ICD-9 | Mapping Flags |
|---|---|---|
| G04.1 | 3441 | 10000 |
Flags format (5 digits): Approximate · No Map · Combination · Scenario · Choice List. Source: CMS 2017 GEMs (final version).
Codes Adjacent To G04.1
Other codes in section G00-G09 (Inflammatory diseases of the central nervous system).
ICD-10 G04.1, Billing FAQ
Is ICD-10 code G04.1 billable? +
Yes, G04.1 is a billable ICD-10-CM code that can appear as a primary or secondary diagnosis on claims.
Does G04.1 affect Medicare Advantage HCC risk adjustment? +
Yes. G04.1 maps to CMS-HCC v28 category 72. Capture this diagnosis annually for accurate Medicare Advantage risk score.
Is G04.1 a CC or MCC for inpatient DRG? +
Yes, this code is designated as CC. Documenting as a secondary diagnosis on inpatient claims can shift the DRG to a higher-weighted category.
What CPT codes are commonly billed with G04.1? +
Procedures frequently paired with G04.1 include: 29405, 95992, 29280, 97010, 29515.
What ICD-9 codes does G04.1 map to? +
Per CMS GEMs, G04.1 maps to ICD-9 codes: 3441. Useful for legacy data review and historical claim analysis.
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Reviewed by the PayerReady Medical Coding Team
Verified against the CMS 2026 code set on June 1, 2026.
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