The Natural History and Muscle Fatigability of Patients With Congenital Myopathies.

Core myopathies (CCD/MmD), nemaline myopathies (NEM) and centronuclear myopathies (CNM) are three types of rare congenital myopathies. Not much is known about the natural history and no curative treatment is available for these groups. Also patients report fatigability as one of their symptoms. The goal of this observational study is to study the natural history during 24 months to achieve trial readiness and to study the muscle fatigability in CCD/MmD, NEM and CNM.