ICD-10 Code G12.8 – Other spinal muscular atrophies and related syndromes (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code G12.8 – Other spinal muscular atrophies and related syndromes
What it is
This code identifies spinal muscular atrophy or a related neuromuscular syndrome that does not fit a more specific ICD-10 category. Use it when documentation names an atypical or other specified form of motor neuron or anterior horn cell disease.
Clinical signs
Clinical features vary; refer to documentation. Commonly documented findings include progressive muscle weakness, hypotonia, muscle wasting, and reduced reflexes, with possible involvement of bulbar or respiratory muscles in some cases.
When to use this code
Use G12.8 when the provider documents “other spinal muscular atrophy,” “related syndrome,” or a named condition that is not indexed to a more specific code. It may also apply when the record clearly indicates a spinal muscular atrophy variant but does not support a more specific subtype. Check documentation if the diagnosis is uncertain.
Do not use for
Do not use this code for a specific spinal muscular atrophy subtype that has its own code, or for nonspecific muscle weakness without a confirmed diagnosis. If the record only suggests a disorder, check documentation.
Coding tip
Match the exact provider wording and confirm whether a more specific G12 code applies before defaulting to G12.8.