High risk of bone fractures in boys with Duchenne Muscular Dystrophy

A recent study has revealed that young boys with Duchenne muscular dystrophy (DMD) have a higher rate of bone fractures than children without the muscle wasting condition.

Fractures are more likely to occur in lower limbs and consequently decrease a patients’ ability to walk, and potentially lead to wheelchair dependence.

DMD is characterized by progressive deterioration of the muscles, because of muscle inflammation, fat infiltration and fibrosis (excessive deposits of connective tissue).

Currently, the only intervention that produces a lasting change in the progression of DMD is glucocorticoid (GC) therapy, which is a steroid hormone-based therapy with anti-inflammatory effects.

Whilst short-term use of GC leads to an improvement of muscle function and strength, long-term usage protects upper limb function and cardiac function, and reduces the risk of scoliosis (spinal curvature).

However, prolonged treatment has been associated with abnormalities of growth and skeletal development.

The study found that among 91 boys with DMD, 51 per cent were wheelchair dependent, two-thirds (65 per cent) were on GC therapy, a quarter of patients had been treated with GC at some point in the past and only 10 per cent had never received GC treatment.

Researchers indicated that almost half (48 per cent) of the patients had at least one fracture, and by the age of 12.8 years old, one out of every two boys developed a first symptomatic fracture.

“When compared to the prevalence of fracture of nine per cent reported in a large cohort of healthy children in the United Kingdom, the prevalence of fracture in DMD in the current study (48 per cent) is clearly much higher,” investigators said.

As a result of these findings, researchers are urging for there to be an increased awareness of the need for proper bone monitoring and routine pubertal assessment in DMD boys.