Also called Roussy-Levy syndrome, this is a hereditary condition characterized by a loss of muscular coordination and progressive atrophy of the muscles and deformation of the skeleton. The atrophy and other muscular symptoms seem to be caused by a neurological defect. Symptoms first appear in early childhood and progress slowly through life. Affected persons have an impaired equilibrium, making walking or standing difficult, and lose their reflexes in the knees and ankles. There may be severe scoliosis and clubfoot.

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