Examination shows symmetric proximal weakness. Serum CK is 500. EMG is myopathic. A 20 year old male is admitted to the cardiac service for repeated syncope. His mother died suddenly several years ago.
Exam shows scapular winging, symmetric weakness in the biceps and triceps, and elbow contractures.
Serum CK is 426. A 5 year old male is evaluated for slow motor development. He was normal until 3 years of age. Examination shows large calves, proximal weakness, waddling gait and difficulty arising from the floor. Serum CK is 11,000.