| A rare genetic skeletal muscle disease with characteristics of neonatal to childhood onset of slowly progressive muscle weakness and atrophy primarily affecting the lower limbs, joint contractures, kyphosis or lordosis of the spine, lateral tongue atrophy, and pes equinus. In addition progression to upper limb involvement, facial weakness, language impairment, intellectual disability, and behavioral abnormalities has been reported. Muscle biopsy shows myopathic changes with increased fiber size variation, internalized nuclei, fiber atrophy, as well as rod structures and core targetoid defects. |
