Charcot-Marie-Tooth Disease

39-year-old female with chronic low back pain and lower extremity weakness. There is linear thickening of several cauda equina equina extending from the level of the conus medullaris to the lumbosacral junction. The nerve thickening extends through the level of the neural foramen to the proximal lumbosacral plexus on the right and left. There is significant paraspinal muscle atrophy and fatty replacement. There was no suspicious enhancement (images not shown). The differential for cauda equina thickening includes Guillain-Barre syndrome, Chronic Inflammatory Polyneuropathy, Charcot-Marie-Tooth disease otherwise known as Hereditary Motor and Sensory Neuropathy, Arachnoiditis, Meningitis and Leptomeningeal Carcinomatosis. This patient had a known diagnosis of Charcot-Marie-Tooth disease. CMT is the most common inherited neuropathy of lower motor neurons. It is most frequently autosomal dominant with the first symptoms occurring in childhood. Nerve roots are typically hypertrophic with an onion bulb sign representing hypertrophic demyelination. Look for denervation injury in the adjacent musculature, as in this case.