Myopathies

Question 1

Milder form of duchenne’s

Answer 1

Becker’s muscular dystrophy

Question 2

Pathophysiology of duchennne’s muscular dystrophy

Answer 2

Mutation dystrophin gene on X chromosome → sk muscle lacks protein dystrophin (provides structural stability) → leakage of Calcium into muscle cell → calcium activate proteases that damage muscle → weakness and fibrosis of PROXIMAL muscles

Question 3

Clinical features of duchenne’s (2)

Answer 3

Large calves

Gower’s sign (weak prox mm)