This physical finding was first noticed when a patient was 10. He had early complaints of frequently sprained ankles and difficulty running and keeping up with peers. He was always clumsy when walking but is still able to ambulate. Recently, he's noticed atrophy of the hand muscles too. There is a family history of this disease following an autosomal dominant pattern. The life expectancy of affected individuals is normal. On exam, you note loss of proprioception and vibration in the lower extremities.
Challenge: What is your diagnosis? (Why is this case called "Dental"?)
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