2022 ICD-10-CM Code G12.9

Spinal muscular atrophy, unspecified

Version 2021

Valid for Submission

ICD-10:G12.9
Short Description:Spinal muscular atrophy, unspecified
Long Description:Spinal muscular atrophy, unspecified

Code Classification

  • Diseases of the nervous system (G00–G99)
    • Systemic atrophies primarily affecting the central nervous system (G10-G14)
      • Spinal muscular atrophy and related syndromes (G12)

G12.9 is a billable diagnosis code used to specify a medical diagnosis of spinal muscular atrophy, unspecified. The code G12.9 is valid during the fiscal year 2022 from October 01, 2021 through September 30, 2022 for the submission of HIPAA-covered transactions.

The ICD-10-CM code G12.9 might also be used to specify conditions or terms like distal hereditary motor neuropathy type 1, distal spinal muscular atrophy, spinal muscular atrophy or spinal muscular atrophy with progressive myoclonic epilepsy.

Unspecified diagnosis codes like G12.9 are acceptable when clinical information is unknown or not available about a particular condition. Although a more specific code is preferable, unspecified codes should be used when such codes most accurately reflect what is known about a patient's condition. Specific diagnosis codes should not be used if not supported by the patient's medical record.

Index to Diseases and Injuries

The Index to Diseases and Injuries is an alphabetical listing of medical terms, with each term mapped to one or more ICD-10 code(s). The following references for the code G12.9 are found in the index:

Approximate Synonyms

The following clinical terms are approximate synonyms or lay terms that might be used to identify the correct diagnosis code:

Clinical Information

Convert G12.9 to ICD-9 Code

The General Equivalency Mapping (GEM) crosswalk indicates an approximate mapping between the ICD-10 code G12.9 its ICD-9 equivalent. The approximate mapping means there is not an exact match between the ICD-10 code and the ICD-9 code and the mapped code is not a precise representation of the original code.

Information for Patients


Spinal Muscular Atrophy

What is spinal muscular atrophy (SMA)?

Spinal muscular atrophy (SMA) is a group of genetic diseases that damages and kills motor neurons. Motor neurons are a type of nerve cell in the spinal cord and lower part of the brain. They control movement in your arms, legs, face, chest, throat, and tongue.

As the motor neurons die off, your muscles start to weaken and atrophy (waste away). The muscle damage gets worse over time and can affect speaking, walking, swallowing, and breathing.

What are the types of spinal muscular atrophy (SMA) and what are their symptoms?

There are different types of SMA. They are based on how serious the disease is and when the symptoms start:

What causes spinal muscular atrophy (SMA)?

Most types of SMA are caused by a change in the SMN1 gene. This gene is responsible for making a protein that the motor neurons need to be healthy and to function. But when part of the SMN1 gene is missing or abnormal, there isn't enough protein for the motor neurons. This causes the motor neurons to die off.

Most people have two copies of the SM1 gene - one from each parent. SMA normally only happens when both copies have the gene change. If only one copy has the change, there usually aren't any symptoms. But that gene could be passed down from parent to child.

Some of the less common types of SMA may be caused by changes in other genes.

How is spinal muscular atrophy (SMA) diagnosed?

Your health care provider may use many tools to diagnose SMA:

Parents who have a family history of SMA may want to do a prenatal test to check to see whether their baby has an SMN1 gene change. An amniocentesis or in some cases a chorionic villi sampling (CVS) is used to get the sample for testing.

In some states, genetic testing for SMA is part of newborn screening tests.

What are the treatments for spinal muscular atrophy (SMA)?

There is no cure for SMA. Treatments can help manage symptoms and prevent complications. They may include

NIH: National Institute of Neurological Disorders and Stroke


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Code History

  • FY 2021 - No Change, effective from 10/1/2020 through 9/30/2021
  • FY 2020 - No Change, effective from 10/1/2019 through 9/30/2020
  • FY 2019 - No Change, effective from 10/1/2018 through 9/30/2019
  • FY 2018 - No Change, effective from 10/1/2017 through 9/30/2018
  • FY 2017 - No Change, effective from 10/1/2016 through 9/30/2017
  • FY 2016 - New Code, effective from 10/1/2015 through 9/30/2016 (First year ICD-10-CM implemented into the HIPAA code set)