Amyotrophe

Amyotrophe is a term used in neurology to describe muscle wasting that results from denervation, or loss of motor neuron input to muscle fibers. The word derives from Greek roots meaning without nourishment of the muscle. In English, the related terms amyotrophic or amyotrophy describe the same concept, and amyotrophe is often encountered in regional or historical usage. It is not a single disease but a descriptive pattern of muscle atrophy.

Cause and scope: Amyotrophe describes neurogenic muscle atrophy seen in a range of motor neuron and nerve disorders. It is commonly associated with conditions such as amyotrophic lateral sclerosis, spinal muscular atrophy, poliomyelitis sequelae, peripheral nerve injuries, and chronic radiculopathies. The underlying issue is loss of motor neuron input, with subsequent muscle fiber atrophy and changes in muscle fiber composition.

Pathophysiology and clinical features: Denervation leads to reduced muscle strength and visible wasting. Early stages may show fasciculations or short-segment weakness, progressing to broader muscle loss. Reflexes may be diminished or absent in affected areas. The pattern of involvement—proximal or distal, focal or generalized—helps distinguish neurogenic atrophy from primary muscle disease.

Diagnosis and management: Diagnosis relies on clinical assessment supported by electromyography and nerve conduction studies to demonstrate denervation. Imaging and laboratory tests help identify the underlying cause. Management focuses on treating the root condition, preventing complications, and providing supportive care such as physical and occupational therapy, nutritional support, and respiratory management when needed.

Prognosis: The outlook varies with the underlying diagnosis and severity of denervation. Neurogenic atrophy often indicates a progressive process, though the course can differ substantially between conditions.