LAUSR

A 44-year-old Caucasian man presented with a 7-year history of upper and lower limb muscle fasciculations and cramps, progressive asymmetric weakness, muscle atrophy, and length-dependent sensory loss. His parents (deceased), 3 older siblings, and 3 children had no history of neurologic symptoms, including weakness and sensory symptoms, with the exception of cramps in the mother. He was not taking any medication known to cause neuropathy or myopathy. On examination, there was right greater than left shoulder girdle muscle weakness and atrophy (Medical Research Council grades 3/5 and 4/5), intrinsic left hand muscle weakness (4+/5) with atrophy, asymmetric pelvic girdle (4/5 right, 3/5 left), and left foot dorsiflexor weakness (4+/5). Strength of neck flexor and extensors, and axial muscles, was normal. He had bilateral calf muscle atrophy and weakness as suggested by his inability to stand on toes (figure, A–C). He was areflexic. Sensory examination revealed distal vibration and pinprick deficits in the upper and lower limbs in a length-dependent fashion. He had bilateral pes cavus.