Question: Encounter notes indicate that the physician treated a patient with “hereditary ataxia.” What is ataxia and how do I choose an ICD-10 code for it? Tennessee Subscriber Answer: Ataxia is a condition that affects a person’s coordination and balance. It can cause difficulties with walking, speaking, and performing fine motor tasks. Ataxia can be caused by various factors, such as genetic disorders, head trauma, stroke, or certain medications. Dx coding: For hereditary ataxia patients, you’ll choose from one of the following codes. (Note, even though a few of the codes don’t contain the word “ataxia,” they are all listed under the G11.- [Hereditary ataxia] heading.)