What is Limb-Girdle Muscular Dystrophy (LGMD)?

Limb-girdle muscular dystrophy (LGMD) is a group of diseases characterized by progressive weakness and muscle atrophy mainly involving the shoulder girdle and the pelvic girdle, collectively called the limb girdle. LGMD has many subtypes with different causal genes.

Signs, Symptoms and Progression

The common features of the LGMDs are the weakness and atrophy of the limb-girdle muscles. The brain, the intellect, and the senses are usually unaffected in LGMD. The age of onset, and the speed and severity of disease progression can vary.
Typical symptoms include:
  • A ‘waddling’ gait while walking
  • Difficulty getting out chairs, rising from a seat, or climbing stairs
  • Difficulty reaching over the head, holding the arms outstretched, or carrying heavy objects
Additional symptoms in some LGMD subtypes:
  • Heart problems, including weakness of the heart muscle (cardiomyopathy) and abnormal transmission of signals that regulate the heartbeat (conduction abnormalities or arrhythmias)
  • Breathing problems
  • Joint stiffness, muscle cramps, enlargement of calf muscles

Causes and Inheritance

There are more than 30 types of LGMD, classified by the different causal genes. Depending on the genetic cause, LGMD can be inherited in an autosomal dominant (type 1) or an autosomal recessive (type 2) pattern.

Diagnosis

The diagnosis process of any muscle dystrophy often starts with a detailed knowledge of the patient’s symptoms, person and family healthy history and a complete physical examination. Other special tests that may be used include nerve conduction studies, electromyography (EMG), blood tests for creatine kinase, and muscle biopsy.
Genetic testing, usually using a blood sample, can be used to confirm the diagnosis and to identify a specific subtype for some forms of LGMD. A known genetic cause can help to predict the likely course of a disease, and to assess the risk of passing on the disease to the next generation.

Treatments

Currently, there is no cure for LGMD. The management is supportive, with the goal of maintaining mobility and functional independence, managing associated complications, and maximizing quality of life. Treatment options may include physical and occupational therapy, assistive devices, surgery to correct skeletal abnormalities such as scoliosis, and regular monitoring and heart and respiratory functions.

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