By Victor Dubowitz, BSc, MD, PhD, FRCP, DCH, Professor of Paediatrics, Department of Paediatrics and Neonatal Medicine, Imperial College Faculty of Medicine, Hammersmith Hospital, London, UK; and Caroline A. Sewry, BSc, PhD, FRCPath, Professor of Muscle Pathology, Dubowitz Neuromuscular Centre, Imperial College Faculty of Medicine, Hammersmith Hospital, London, UK; Centre for Inherited Neuromuscular Disorders, Department of Histopathology, Robert Jones and Agnes Hunt Orthopaedic Hospital, Oswestry, UK |