Hereditary neuromuscular diseases are a large heterogeneous group of diseases caused by a genetically determined involvement of the neuromuscular system (Fig. 17.1, 17.2). The disease presents with progressive muscle atrophy, muscle weakness, muscle paresis.

Fig. 17.1. Myoneural synapse: 1 — myelin sheath; 2 — axon; 3 — node of Ranvier; 4 — presynaptic membrane; 5 — synaptic cleft; 6 — postsynaptic membrane; 7 — lemmocyte (Schwann cell); 8 — mitochondria; 9 — transverse tubular system; 10 — myofibrils; 11 — nucleus; 12 — sarcoplasm

Fig. 17.2. Main types of muscle atrophy: 1 — Werdnig-Hoffmann type I spinal muscular atrophy; 2 — Dejerine–Sottas interstitial hypertrophic neuropathy; 3 — neural amyotrophy (Charcot–Marie-Tooth progressive neural peroneal muscle atrophy); 4 — Friedreich’s disease (familial spinal ataxia); 5 — myasthenia gravis; 6 — paroxysmal myoplegia (familial periodic paralysis); 7 — progressive muscular dystrophy; 8 — (non-atrophic) myotonia congenita (Thomsen disease); 9 — atrophic myotonia; 10 — amyotonia congenita (Oppenheim’s disease); 11 — Duchenne–Aran chronic progressive familial spinal amyotrophy of adults; 12 — Charcot amyotrophic lateral sclerosis. The green color indicates the onset of the disease in childhood, red — in adolescence, blue — in adulthood, purple — in the elderly

The diagnosis is based on the age of the onset of clinical manifestations, localization and progression of the myodystrophic process (the presence or absence of pseudohypertrophy, fascicular twitching, episodes of muscle weakness, sensitivity disorders), family history, and type of inheritance of the disease.

Hereditary neuromuscular diseases include:

• progressive muscular dystrophy (primary muscle diseases);
• hereditary polyneuropathies or neural amyotrophy (diseases with a predominant primary involvement of the motor and sensory fibers of the peripheral nerves);
• spinal amyotrophy (diseases with primary involvement of the motor neurons of the anterior horns of the spinal cord).