# Unilateral Calf Atrophy: A Case Series of Clinical and Electrodiagnostic Findings With a Review of the Literature

## TL;DR

This paper presents four cases of one-sided calf muscle shrinkage and explains how tests like nerve studies and ultrasounds help identify the cause.

## Contribution

The study provides a case series and review of diagnostic approaches for unilateral calf atrophy.

## Key findings

- EDX studies showed denervation changes in two patients with chronic neurogenic atrophy.
- An ultrasound identified a Baker’s cyst compressing the tibial nerve in one patient.
- EDX and US are effective in distinguishing causes of asymmetric calf atrophy.

## Abstract

Unilateral calf atrophy may result from several medical conditions, such as lumbar radiculopathy, asymmetric myopathy/dystrophy, a Baker’s (popliteal) cyst leading to tibial nerve compression, and disuse atrophy. We present a case series of four patients with unilateral calf atrophy, including chronic neurogenic atrophy (benign focal amyotrophy, one patient), tibial nerve compression at the popliteal fossa by a Baker’s cyst (one patient), and disuse atrophy (two patients). All four patients underwent electrodiagnostic (EDX) studies, and two of them had denervation changes of the gastrocnemius. One patient underwent an ultrasound (US), which revealed a large cyst in the popliteal fossa causing compression of the tibial nerve. The differential diagnosis of unilateral calf atrophy as well as diagnostic techniques to confirm the underlying pathology are described. EDX and US studies are useful in differentiating between the varied conditions that may cause asymmetric calf muscle wasting.