Not a common feature of Duchene muscular dystrophy is?

ANSWER: (C) Distal muscle involvementREF: Nelson's 18th ed p. 2541Duchene muscular dystrophy is the most common hereditary neuromuscular disease affecting all races and ethnic groups. The abnormal gene is on the X chromosome at the Xp21 locus and is one of the largest genes identified.Becker muscular dystrophy is the same fundamental disease as Duchene dystrophy, with a genetic defect at the same locus, but clinically it follows a milder and more protracted course.Duchene recognized most of the characteristic clinical features in 1861: hypertrophy of the calves, progressive weakness, intellectual impairment, and proliferation of connective tissue in muscleClinical featuresGower's sign positivePseudo hypertrophy of calvesLoss of muscle strength is progressiveProximal muscles and neck flexors are involved moreLeg involvement more severe than armContractures of heels and illiotibial tract by 6 yrs. AgeProgressive scoliosis ComplicationsCardiomyopathy and CHFIntellectual impairmentChest deformity