Fascicular atrophy
Selective wasting of individual muscle fascicles creating a scalloped muscle border appearance. Indicates chronic denervation or specific myopathic processes.
Full Definition
Fascicular atrophy refers to the selective atrophy of individual muscle fascicles within a muscle belly, creating a characteristic scalloped or undulating appearance of the muscle border on imaging studies or gross examination. This pattern occurs in chronic neurogenic conditions where motor units are lost over time, or in specific myopathic processes affecting fascicular architecture. Unlike diffuse muscle atrophy, fascicular atrophy creates an irregular muscle contour that is particularly evident on MRI or ultrasound imaging. The pattern and distribution of fascicular atrophy can provide diagnostic clues about the underlying neuromuscular condition.
Usage
Usage note: Distinguish from overall muscle atrophy. Document specific muscles affected and imaging modality used.
In Context
- "MRI revealed fascicular atrophy in the posterior compartment of both thighs, consistent with chronic denervation." — Radiology report
- "The vastus medialis showed prominent fascicular atrophy on ultrasound, creating the characteristic scalloped appearance." — Neuromuscular ultrasound report