FKRP and neuromuscular disease caused by qualitative or quantitative defects of alpha-dystroglycan: Hierarchical clustering of patients according to the individual thigh muscles revealed that most patients with sarcoglycanopathies or LGMD2I can be distinguished from dystrophinopathies by muscle MRI according to the presence or absence of the concentric fatty infiltration pattern or trefoil with single fruit sign, indicating that these two distinctive patterns are of high differential value in distinguishing sarcoglycanopathies or FKRP-associated dystroglycanopathy from dystrophinopathies.