Atypical Proximal Cervical Spondylotic Amyotrophy: Case Report Demonstrating Clinical/Imaging Discrepancy

PURPOSE: The aim of this study was to present a novel case of unilateral proximal cervical spondylotic amyotrophy (CSA) with contralateral spinal cord compression, which is subject to misdiagnosis and missed diagnosis. BACKGROUND: CSA is the rare form of cervical spondylosis, which is characterized by severe muscle atrophy in the upper extremities. It can be classified in the proximal subtype and the distal subtype. The etiology, pathophysiology and treatment of CSA are still controversial. METHODS: A rare case of atypical proximal CSA, who presented with left shoulder and arm weakness, but cervical magnetic resonance imaging (MRI) showed large right paracentral disc herniation in the C4-5 level. Twelve weeks after undergoing anterior cervical discectomy and fusion technique in C4-5 level, the patient’s symptoms obviously recovered. CONCLUSION: The opposite sides between disc herniation and clinical symptoms of upper extremity may be attributed to C5 ventral rootlet becoming stretched caused by spinal cord rotation or shift to the opposite side.