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Updated: Jul 28, 2026
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Quantitative Magnetic Resonance Imaging of Skeletal Muscle Disease
Published on: December 18, 2016
Denervation hypertrophy of muscle: MR features
C A Petersilge1, M N Pathria, A Gentili
1Department of Radiology, University Hospitals of Cleveland, OH 44106, USA.
Journal of Computer Assisted Tomography
|July 1, 1995
Summary
Denervation hypertrophy causes paradoxical muscle enlargement. Magnetic resonance imaging (MRI) can distinguish true hypertrophy from pseudohypertrophy, aiding diagnosis of underlying neurologic conditions.
Area of Science:
- Neurology
- Radiology
- Musculoskeletal Imaging
Background:
- Denervation hypertrophy, a paradoxical muscle enlargement post-nerve loss, is underrepresented in radiology literature.
- Understanding its imaging features is crucial for accurate diagnosis.
Purpose of the Study:
- To describe the magnetic resonance (MR) imaging appearance of true and pseudohypertrophy in muscles affected by denervation.
Main Methods:
- Retrospective review of clinical data and MRI findings in three patients with denervation hypertrophy.
- Causes of denervation included spinal stenosis, herniated thoracic disc, and spina bifida with tethered cord.
Main Results:
- One patient showed true hypertrophy, another pseudohypertrophy, and one had both.
- Abnormal muscles exhibited increased volume, well-defined margins, and normal contour.
- True hypertrophy appeared isointense; pseudohypertrophy showed interspersed fat on MRI.
Conclusions:
- MRI can differentiate muscle hypertrophy from neoplasm as a cause of palpable masses.
- Enlarged extremities on MRI may indicate underlying neurologic processes like denervation hypertrophy.
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