Short answer · Medically reviewed summary · Last updated: 2026-05-08
Congenital Fiber Type Disproportion (CFTD) is typically classified under the ICD-10 code G71.2 (Congenital myopathies), as there is no unique, specific code dedicated solely to this condition. Similarly, under the ICD-9-CM classification system, Congenital Fiber Type Disproportion is categorized under 359.0, which covers congenital hereditary muscular dystrophy and other congenital myopathies. Why is there no unique ICD code for Congenital Fiber Type Disproportion? In medical coding, rare conditions like Congenital Fiber Type Disproportion are often grouped into broader categories because they are ultra-rare.
ICD10 code of Congenital Fiber Type Disproportion and ICD9 code
ICD-10 and ICD-9 codes for Congenital Fiber Type Disproportion, with classification details for clinicians, coders and patients.
Congenital Fiber Type Disproportion (CFTD) is typically classified under the ICD-10 code G71.2 (Congenital myopathies), as there is no unique, specific code dedicated solely to this condition. Similarly, under the ICD-9-CM classification system, Congenital Fiber Type Disproportion is categorized under 359.0, which covers congenital hereditary muscular dystrophy and other congenital myopathies.
Why is there no unique ICD code for Congenital Fiber Type Disproportion?
In medical coding, rare conditions like Congenital Fiber Type Disproportion are often grouped into broader categories because they are ultra-rare. Since Congenital Fiber Type Disproportion is a form of congenital myopathy characterized by a specific muscle biopsy finding—where type 1 muscle fibers are significantly smaller than type 2 fibers—clinicians use the broader G71.2 code to ensure the condition is recognized within the healthcare system for billing and clinical documentation.
What are the primary clinical features of Congenital Fiber Type Disproportion?
Patients living with Congenital Fiber Type Disproportion often present with muscle weakness, hypotonia (low muscle tone), and potential skeletal deformities. At DiseaseMaps.org, 17 people with Congenital Fiber Type Disproportion have joined our community, highlighting the importance of shared experiences in navigating this diagnosis. Common clinical manifestations include:
- Generalized muscle weakness, often most prominent in the proximal muscles.
- Congenital hip dislocation or scoliosis.
- Respiratory insufficiency requiring monitoring.
- High-arched palate or elongated face.
How is a diagnosis of Congenital Fiber Type Disproportion confirmed?
A definitive diagnosis is usually established through a muscle biopsy, which remains the gold standard for identifying the characteristic fiber size discrepancy. Genetic testing is increasingly used to identify causative mutations in genes such as ACTA1, SEPN1, or TPM3, which are associated with the Congenital Fiber Type Disproportion phenotype. Because the condition is heterogeneous, a clinical geneticist is essential for interpreting these complex genetic findings.
Next steps
- Consult with a neuromuscular specialist or pediatric neurologist for ongoing management.
- Connect with the 17 other community members at DiseaseMaps.org to share management strategies.
- Schedule a consultation with a genetic counselor to discuss inheritance patterns for your family.
- Monitor respiratory function regularly through a pulmonologist specializing in neuromuscular diseases.
Medical disclaimer: This information is for educational purposes only and does not replace professional medical advice, diagnosis, or treatment.
References
- Orphanet: Congenital fiber-type disproportion (ORPHA:166024)
- NIH GARD: Congenital fiber-type disproportion
- OMIM: Congenital fiber-type disproportion (Entry #255310)
- Muscular Dystrophy Association (MDA): Resources on Congenital Myopathies
