Limb-girdle muscular dystrophy (LGMD) is a group of health conditions that can cause weakness and deterioration of the muscles, particularly in the hip and shoulder areas.
LGMD is a genetic condition, which means a person can inherit it from one or both parents.
This article discusses LGMD in more detail, including symptoms, causes, treatments, diagnosis, and more.
One of the first symptoms of LGMD is typically a weakening of the muscles in the hip and shoulder girdles.
The hip girdle is a ring-like bone structure in the pelvic area, consisting of the pelvis, the top of the thigh bones, and the base of the spine. The shoulder girdle is the bony structure in the shoulders, consisting of the shoulder blade and the collar bone.
A person with LGMD may have difficulty standing up from a chair, climbing the stairs, reaching arms above their head, and carrying heavy objects.
Other symptoms can include:
- changes to the way a person walks, such as waddling or walking on the balls of the feet
- loss of muscle mass
- lower back pain
- muscle weakness in the thighs, lower legs, shoulders, and arms
- difficulty running
- changes in posture due to a weakening of muscles
- protruding shoulder blades due to a weakening of the shoulder muscles
- stiffness in the hip, knee, ankle, and elbow joints
- enlargement of the calf muscles
- difficulty breathing due to the weakening of the heart muscle
How common is limb-girdle muscular dystrophy?
According to the Genetic and Rare Diseases Information Center (GARD), LGMD is a rare condition affecting fewer than 50,000 people in the United States.
Learn more about muscular dystrophy.
The main cause of LGMD is the mutation of certain genes responsible for maintaining and repairing muscles. These gene mutations are genetic, which defines when a person inherits them from one or both parents.
There are two ways a person can inherit LGMD. The
The less common inheritance pattern for LGMD is autosomal dominant, which occurs when only one parent passes on the gene mutation.
According to the Muscular Dystrophy Association, there is ongoing research into what causes the subtypes of LGMD that do not have a proven direct cause.
LGMD subtypes are the different types of gene mutations that can lead to LGMD.
Research from 2018 suggests there are over 30 subtypes of LGMD, each presenting differently. The age at which a person experiences symptoms, how quickly the condition progresses, and how severe the symptoms are can vary widely between subtypes.
According to the National Library of Medicine, the most common subtype is type 2A. It currently affects approximately 30% of people with LGMD.
The exact progression of LGMD can be difficult to predict, as it is variable for each subtype. A person may only ever experience mild symptoms that do not occur until adulthood and progress slowly. However, a person may experience more severe symptoms from childhood and progress quickly.
A person with LGMD typically experiences muscle weakness beginning in the hip and shoulder areas and progressing to the muscles in the lower arm, lower leg, hands, feet, trunk, and head. This may lead to a person requiring mobility assistance and wheelchair dependence.
Less common progression of LGMD can include a decline in heart and respiratory function. This can progress to heart failure or difficulty breathing without assistance.
A 2023 study suggests that approximately 63% of people with LGMD will experience a loss of mobility, and 34% of people will experience heart or breathing issues.
As LGMD is a genetic condition, it is important that a person receives an accurate diagnosis so their family can receive the correct genetic advice.
To diagnose LGMD, a doctor will assess any symptoms present and take a full medical history. A doctor may also perform various tests, including:
- blood tests, which check for high levels of the enzyme creatine kinase and certain muscle proteins
- muscle biopsies
- electromyography, which involves inserting a needle electrode into the muscle to test whether the cause of weakness is LGMD or nerve damage.
- genetic testing to identify the presence of certain gene mutations
- scans to assess heart function, such as an echocardiogram, electrocardiogram, or electromyogram
There is currently
- Low impact exercise such as swimming may help the muscle retain tone without the stress of impact.
- Physical therapy may help with mobility and strengthening the large muscle groups.
- Occupational therapy may help a person adapt to performing daily tasks more easily.
- Assistive devices such as a cane, wheelchair, or scooter may help support a person to remain as mobile as possible.
- Cardiac devices can help monitor and regulate heart rate.
- Installing ventilation systems may help if a person has trouble breathing.
- Maintaining a moderate weight may put less stress on the weakening muscles.
- Diet and nutrition therapy may help people meet all their nutritional needs if they have difficulty swallowing.
What is the life expectancy of a person with limb-girdle muscular dystrophy?
Life expectancy for a person with LGMD can vary depending on the subtype and the muscles it affects. For example, life expectancy is typically within a standard range if a person has LGMD without weakening the heart or breathing muscles.
However, if a person experiences a weakening of the heart or breathing muscles, this may reduce life expectancy.
What is the gait of limb-girdle muscular dystrophy?
Research suggests that people with LGMD typically have a distinct “waddling” gait, which may often be the first symptom they experience.
Limb-girdle muscular dystrophy (LGMD) describes a group of rare genetic conditions affecting the hip and shoulder girdle muscles.
LGMD typically causes muscle weakness and deterioration and can also affect other muscles in the body as the condition progresses.
There are over 30 subtypes of LGMD, each involving different genetic mutations.
There is no known cure for LGMD. However, a person can help manage symptoms with physical therapy, occupational therapy, low impact exercise, and mobility aids.