History
The course is progressive in all forms of muscular dystrophy (always progressive). It begins with a weakening of the muscles in the pelvic girdle area and then spreads further. Initially, weakness in the leg muscles is noticeable, as well as difficulty in walking.
Fat and connective tissue is then formed from the muscles, resulting in a reduction in strength. This leads to a decrease in muscle stability in the trunk and legs, which also impairs the remaining mobility. It is becoming increasingly difficult to straighten up and to change the position from sitting to standing and from lying down to sitting.
As already described for Duchenne, muscular dystrophy starts in early childhood. The course of Duchenne progresses more rapidly so that already at the age of 12, complications of the organs can occur. This is the difference to the Becker-Kiener form which has a longer course. The weakness starts only in the course of childhood from the age of 6 and the patients reach a high age of up to 60 years.
Life expectancy
Since Duchenne muscular dystrophy starts in early infancy and progresses faster, life expectancy is shorter in this form. Becker-Kiener patients can already reach the age of 60 until difficulties with the organs occur. In general, muscular dystrophy is progressive and progresses over the years.
Therefore, life expectancy is prognostically not favorable for the patients. The severity of the disease can vary and does not always have to be severe. The patient may still be independent in adulthood despite muscular dystrophy.
With targeted therapy, the symptoms of the disease can be well treated and the physical condition of the patient can be well maintained. It is also possible to build up some muscle functions well through physiotherapy. However, as soon as Duchenne and Becker-Kiener suffer from complications in the organs, it becomes difficult for the patients and also their life expectancy is lower.
Inheritance
The defect of the X chromosome is not gender-specific. This can affect both boys and girls. However, the disease does not break out in girls, as they can compensate for the genetic defect with their second X chromosome.
Boys, on the other hand, cannot compensate for this with their other Y chromosome. Therefore, muscular dystrophy is almost only found in boys. If a girl were to develop muscular dystrophy, she would have to inherit a defect in the X chromosome of both parents. But this probability is very low.
