Short answer · Medically reviewed summary · Last updated: 2026-04-07
Machado-Joseph Disease, also known as Spinocerebellar Ataxia Type 3 (SCA3), is classified under the ICD-10 code G11.2 (Spinocerebellar ataxia). In the older ICD-9 clinical modification system, it was categorized under 334.0 (Friedreich's ataxia) or 334.8 (Other spinocerebellar diseases), as specific coding for Machado-Joseph Disease did not exist as a unique entry. What is the clinical significance of these medical codes for Machado-Joseph Disease? Medical coding systems are essential for healthcare providers to document, track, and bill for services related to Machado-Joseph Disease.
ICD10 code of Machado-Joseph Disease and ICD9 code
ICD-10 and ICD-9 codes for Machado-Joseph Disease, with classification details for clinicians, coders and patients.
Machado-Joseph Disease, also known as Spinocerebellar Ataxia Type 3 (SCA3), is classified under the ICD-10 code G11.2 (Spinocerebellar ataxia). In the older ICD-9 clinical modification system, it was categorized under 334.0 (Friedreich's ataxia) or 334.8 (Other spinocerebellar diseases), as specific coding for Machado-Joseph Disease did not exist as a unique entry.
What is the clinical significance of these medical codes for Machado-Joseph Disease?
Medical coding systems are essential for healthcare providers to document, track, and bill for services related to Machado-Joseph Disease. Because this condition is a rare, autosomal dominant neurodegenerative disorder, precise coding ensures that patients receive appropriate insurance coverage for specialized care, such as physical therapy, speech therapy, and neurology consultations. While ICD-10 code G11.2 is the primary designation used globally, it is important to note that it captures a broader category of hereditary ataxias, meaning that diagnostic confirmation via genetic testing remains the gold standard for identifying Machado-Joseph Disease specifically.
How is Machado-Joseph Disease diagnosed?
Diagnosis of Machado-Joseph Disease is primarily achieved through molecular genetic testing, which identifies an abnormal expansion of CAG trinucleotide repeats in the ATXN3 gene on chromosome 14q32.1. Before genetic testing, neurologists typically perform a clinical examination to assess for hallmark symptoms, including gait ataxia, ophthalmoplegia (eye movement difficulties), and dystonia. At DiseaseMaps.org, 42 people with Machado-Joseph Disease have shared their experiences, highlighting the diverse age of onset, which typically occurs between 20 and 50 years of age.
What are the key clinical features and progression of the disease?
The progression of Machado-Joseph Disease is highly variable, even within families, often depending on the length of the CAG repeat expansion. Clinicians generally classify the symptoms into distinct types based on the age of onset and the predominant neurological features present. Common clinical manifestations include:
- Progressive Ataxia: Unsteady gait, poor balance, and lack of coordination in limbs.
- Ocular Abnormalities: Bulging eyes (exophthalmos), lid retraction, and slowed saccadic eye movements.
- Motor Symptoms: Muscle stiffness (spasticity), tremors, and involuntary muscle contractions (dystonia).
- Speech and Swallowing: Dysarthria (slurred speech) and dysphagia (difficulty swallowing) which may require speech therapy intervention.
- Sensory Deficits: Loss of sensation in the extremities and peripheral neuropathy.
Is Machado-Joseph Disease hereditary?
Yes, Machado-Joseph Disease follows an autosomal dominant pattern of inheritance. This means that an affected individual has a 50% chance of passing the expanded ATXN3 gene to each of their children. Genetic counseling is strongly recommended for families affected by Machado-Joseph Disease to discuss the implications of genetic testing, the phenomenon of anticipation (where the age of onset may be earlier in successive generations), and reproductive options.
Next steps
- Consult a neurologist or a movement disorder specialist to discuss diagnostic genetic testing.
- Schedule an appointment with a genetic counselor to understand the inheritance pattern of Machado-Joseph Disease within your family.
- Connect with the 42 community members at DiseaseMaps.org to share experiences and find emotional support.
- Inquire about local physical and speech therapy programs specifically tailored for neurodegenerative ataxia.
Medical disclaimer: This information is for educational purposes only and does not constitute medical advice, diagnosis, or treatment; always seek the advice of a qualified physician regarding any medical condition.
