Expanding the phenotype of filamin-C-related myofibrillar myopathy.

We report three patients with a rare filamin C myofibrillar myopathy. They present with atypical symptoms that expand the phenotype of filaminopathy. The new findings are progressive contractures of muscles surrounding the temporomandibular joint, detailed single myofiber histology findings and demonstration of severe affection of paraspinal muscles on MRI.