While working is his garden, a 59-year-old man noticed pain in his neck and shoulders. He had some difficulty holding his head in an upright position and rising from a squat. The referring neurologist had performed an MRI scan of the cervical spine, which was normal. As his CK activity was moderately elevated and the EMG showed fibrillation potentials, myositis was suggested. On referral – six months after disease onset – he also mentioned difficulty climbing stairs. When walking, he experienced cramps in the calves. In recent weeks, he had developed a slurred speech and had problems fastening buttons. He had lost 10 kg (12% of his original weight). Pseudobulbar affect (forced laughter, yawning, or crying) was not mentioned at the time.

A 63-year-old woman was referred because of decreased strength of her right leg manifesting with buckling of the knee for the past five years. Sometimes this led to falls, which made her feel insecure while walking. She experienced some aching in her right heel and in her right knee after long walks. She was able to walk for two hours. She and her husband loved to walk in the mountains, and during those hikes she used a cane. The previous history is relevant because at age 5 years she had suffered from poliomyelitis anterior acuta, which had affected both legs. She had a partial recovery in the sense that she regained normal strength of her left leg and was left with residual weakness of her right leg. She underwent surgery at age 10 years (ankle arthrodesis on the right and epiphysiodesis of the left leg).

When playing slow passages, a 55-year-old professional accordionist noticed painless cramping of the right finger flexors. Treatment with botulinum toxin for suspected dystonia had no effect. In the following months, cramps also occurred at rest, and he had to give up his profession. He also noted twitches in the limb muscles.

An 18-year-old man had noticed progressive painless weakness and a decrease in size of his left forearm and hand for about one year. He was not able to lift objects, and at the gym he had difficulty handling the dumbbells. He had noticed involuntary contractions not only of his forearm muscles, but also of his chest and once in his legs. Previous medical history and family history were unremarkable.