Duchenne muscular dystrophy (DMD) is a genetic condition that causes progressive muscle weakness. It is caused by a mutation in the gene that encodes the dystrophin protein, which is important for muscle fiber integrity. Boys are most commonly affected as it is inherited through the X chromosome. Symptoms usually appear between ages 1-3 and include difficulty walking, running and climbing stairs. As the condition progresses, it affects trunk and shoulder muscles and can lead to an enlarged heart. There is no cure, but treatment focuses on managing symptoms and delaying effects through steroid injections and mobility aids.

1. DUCHENNE MUSCULAR DYSTROPHY
What is Duchenne muscular dystrophy (DMD)?
Duchene muscular dystrophy (DMD) is a severe, progressive, muscle-wasting
disease. It is a genetic condition, which affects the muscles, causing muscle
weakness and muscle become less flexible over time.
It is one of a type of muscular dystrophy from 20 known types.
Age group mostly effected:
It is a serious condition, which starts in early childhood. It mostly effect boys
because of the X gene they receive from one parent.
The muscle weakness is not noticeable at birth, even though the child is born with
the gene, which causes it. The weakness develops gradually, usually noticeable by
the age of three. Symptoms are mild at first but become more severe as the child
gets older.
How DMD develops:
The Duchenne type dystrophy is an X-linked genetic disorder. The cause is a
mutation in the gene that encodes the 427-kDa cytoskeletal protein dystrophin,
which affects the muscles. People with DMD have a shortage of dystrophin in their
muscles. The lack of dystrophin leads to muscle fiber damage and a gradual
weakening of the muscles.

2. Dystrophin is responsible for connecting the cytoskeleton of each muscle fiber to
the underlying basal lamina. The absence of dystrophin stops calcium entering the
cell membrane affecting the signaling of the cell, water enters the mitochondria
causing the cell the burst. In a complex cascading process, that involves several
pathways, increased oxidative stress within the cell damages the sarcolemma
resulting in the death of the cell, and muscle fibers undergo necrosis and are
replaced with connective tissue.

3. Sign and symptoms:
The symptoms usually start around age 1-3 years.
1. Difficulty with walking, running, jumping and climbing stairs.
2. Usually trunk muscles, hip, and shoulder are affected along with lower
extremity more affected.
3. Hand movements are less affected.

4. 4. Toe walking, in this gait pattern, children walk on their toes with feet apart
to help maintain balance, with an increased curve in the lower back.
5. Delay in development of child, i.e. speech delays.
6. The calf muscles may look bulky, although they are not strong.
7. Positive Gower’s sign. (The child may use his hands to help him get up,
looking as if he is climbing up his legs).
8. Frequent falls.
9. Progressive enlargement of heart.
10.Contracture develops, in case of major disability.
Diagnosis:
Diagnosing DMD involves following tests:
1. Physical diagnosis, by checking the child way of walking and running.
Gower’s Sign is a very common physical finding.
2. Blood test, This test is for creatine kinase. Children with DMD always have a
very high level of creatine kinase (about 10-100 times normal).
3. A muscle biopsy involves taking a small sample of a muscle, under local
anesthetic. The sample is examined under a microscope using special
techniques to look at the muscle fibers and the dystrophin protein.
4. Genetic tests are done using a blood sample. The DNA in the blood is tested
to look at the dystrophin gene. This test can diagnose most cases of DMD.
Medical management:
1. No known cure is available, but steroids injections are given as they delay
the dystrophy for some time period.

5. 2. Mobility aids i.e. walkers, standing frames, wheelchairs, and ankle foot
orthosis.