RPN Muscular Dystrophy

Duchenne and Becker muscular dystrophy are dystrophinopathies. Dystrophin helps stabilize the muscle-cell membrane during contraction. When dystrophin is absent or markedly abnormal, repeated contraction injures the sarcolemma, calcium enters the muscle fiber, inflammation and necrosis follow, and muscle is gradually replaced by fat and fibrosis. Duchenne is typically more severe and earlier because functional dystrophin is absent or nearly absent. Becker is usually milder because some partially functional dystrophin remains. For NCLEX-PN (United States), items rarely announce the topic in the first sentence. Anchor to objective data, trajectory, and the safest next step for the role named in the stem before distractors compete.