Definition of Limb-girdle muscular dystrophies:

Limb-girdle muscular dystrophies include at least 18 different inherited disorders, which first affect the muscles around the shoulder girdle and hips. These diseases get worse, and may eventually involve other muscles.

Causes, incidence, and risk factors:

Limb-girdle muscular dystrophies are a large group of genetic diseases in which there is muscle weakness and wasting (muscular dystrophy).

In most cases, both parents must pass on the defective gene for a child to have the disease (autosomal recessive disorder). However, in some rare types only one parent needs to pass on the bad gene to affect the child (autosomal dominant disorder). For some of these conditions, the defective gene has been discovered. For others, the gene is not yet known.

An important risk factor is having a family member with muscular dystrophy.