Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) Emery-Dreifuss muscular dystrophy ?
    ### Response:
    Emery-Dreifuss muscular dystrophy is a condition that chiefly affects muscles used for movement (skeletal muscles) and heart (cardiac) muscle. Among the earliest features of this disorder are joint deformities called contractures, which restrict the movement of certain joints.
    