2026 ICD-10-CM Diagnosis Code G71.21Nemaline myopathy

ICD-10-CM Codes›G00–G99›G70-G73›G71

ICD-10-CM G71.21
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

G71.21 is a billable ICD-10-CM diagnosis code for nemaline myopathy. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026). Coders also document this condition as amish nemaline myopathy. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Myopathies.

Code Identity

ICD-10-CM Code
G71.21
Billable Status
Yes — Valid for Submission
Code Describes
Nemaline myopathy
Short Description
Nemaline myopathy
Same as the full description in the CMS dataset.
Parent Code
G71.2
Congenital myopathies

Code Classification

ChapterG00–G99Diseases of the nervous system
SectionG70-G73Diseases of myoneural junction and muscle
CategoryG71Primary disorders of muscles
This CodeG71.21Nemaline myopathy

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Amish nemaline myopathy
  • Childhood-onset nemaline myopathy
  • Intermediate nemaline myopathy
  • Nemaline myopathy
  • Nemaline myopathy, early onset type
  • Nemaline myopathy, late onset type
  • Progressive weakness of muscle
  • Severe congenital nemaline myopathy
  • Typical nemaline myopathy

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

External Cause of Injuries IndexGuidance

References for this code in the External Cause of Injuries Index.

    • Disease, diseased
      • nemaline body
    • Disease, diseased
      • rod body
    • Myopathy
      • nemaline
    • Myopathy
      • rod (body)

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR NVS018
Myopathies
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Nemaline myopathy

Nemaline myopathy is a disorder that primarily affects skeletal muscles, which are muscles that the body uses for movement.

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Code History & ChangesHistory

Replacement G71.21 replaces the following previously assigned code(s):

  • G71.2 - Congenital myopathies
FY 2021AddedAdded to the ICD-10-CM code setEffective October 1, 2020.
FY 2022–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About G71.21Overview

Is G71.21 (Congenital myopathies) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report nemaline myopathy on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

Footnotes

[1] Chronic - a chronic condition code indicates a condition lasting 12 months or longer and its effect on the patient based on one or both of the following criteria:

  • The condition results in the need for ongoing intervention with medical products,treatment, services, and special equipment
  • The condition places limitations on self-care, independent living, and social interactions.