Muscular dystrophies include a group of severe neuromuscular diseases leading to progressive loss of skeletal muscle, slowly replaced by adipose and connective tissues. This often leads to respiratory and cardiac loss of function which aggravates the progressive decline of motor abilities.
Diagnostic procedures in the neuromuscular field include a standard set of procedures like muscle strength quantification, EMG studies, muscle biopsies and specific procedures which differ depending on the specific type of muscular dystrophy involved.
Muscular dystrophies are mostly genetic diseases, with different hereditary patterns ranging from recessive (i.e. parents may be asymptomatic carriers), autosomal dominant (50% chance of an affected parent transmitting the disease), sex-linked (only males are affected) or mitochondrial transmission (mostly maternally inherited). The age at onset and the progression vary from type to type.
The most common in infancy Duchenne Muscular Dystrophy (DMD) (incidence of 19-29,5 per 100.000 live male births, and a prevalence of 1.7-7.1 per 100.000), and Becker Muscular Dystrophy (BMD) respectively due to a total or partial lack of the protein dystrophin.
In adulthood the most common are Facio-ScapuloHumeral Muscular Dystrophies (FSHD) and the Myotonic Dystrophies (DM1 and DM2) followed by the Limb-Girdle Muscular Dystrophies, Emery-Dreifuss Muscular Dystrophies, and the congenital muscular dystrophies (i.e. a heterogeneous cluster of dystrophies with onset within the first year of life, with variable severity).