Abstract

Denervation from various conditions typically results in muscular atrophy; in contrast, a paradoxical volumetric increase can also rarely occur in affected muscles, which is called denervation pseudohypertrophy. Although this condition may potentially affect any muscle group, it is most commonly seen in the calf muscles. When evaluating patients with painless calf muscle enlargement, denervation pseudohypertrophy is an important differential diagnosis that should be considered. Radiological imaging methods and electromyography (EMG) are useful for differentiating pseudohypertrophy from muscular hypertrophy. Identifying denervation pseudohypertrophy requires multidisciplinary evaluation. Alongside radiological imaging and EMG findings, patient's detailed medical history and physical examination remain essential components of the diagnostic process. In this case report, we aim to present a 73-year-old man with bilateral calf muscle denervation pseudohypertrophy due to S1 radiculopathy, along with the relevant literature.

Keywords: magnetic resonance imaging, denervation, pseudohypertrophy, calf muscles, radiculopathy

Copyright and license

Copyright © 2026 The Author(s). This is an open-access article published by Bolu İzzet Baysal Training and Research Hospital under the terms of the Creative Commons Attribution License (CC BY) which permits unrestricted use, distribution, and reproduction in any medium or format, provided the original work is properly cited.

How to cite

1.
Başdemirci O, Dağıstan E, Başdemirci M. A rare clinical presentation of lumbosacral radiculopathy: Denervation pseudohypertrophy of bilateral calf muscles. Northwestern Med J. 2026;6(1):369-73. https://doi.org/10.54307/2026.NWMJ.161

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