Pathophysiology
Clinical meaning
Duchenne muscular dystrophy (DMD) is an X-linked recessive disorder caused by mutations in the dystrophin gene, resulting in absence of the dystrophin protein needed for muscle fiber stabilization. Without dystrophin, the muscle cell membrane becomes fragile and susceptible to damage during contraction. Repeated cycles of muscle damage, inflammation, and attempted regeneration eventually lead to replacement of muscle fibers with fat and connective tissue. The disease primarily affects boys, with onset between ages 2-5 years. Muscles of the proximal lower extremities and pelvis are affected first. The nurse monitors mobility, assists with fall prevention, and reports changes in motor function or respiratory status.