ИСТИНА

Introduction Cervical spondylotic myelopathy may lead to slowly progressive benign form of motor neuron disease that affects upper extremity distal and proximal muscles. The gradual onset, progressive disease course and isolated motor dysfunction can usually mimic early stages of the amyotrophic lateral sclerosis (ALS). Methods Case report Results A 47-year-old woman presented with the severe weakness and hypotrophy in both arms (S>D), neck restraint movement and cervicalgia, that appeared 3 years ago and were slowly progressing (Fig. 1a, b). Nerve conduction study revealed rough axonal dysfunction of ulnar, axillary and musculocutaneous nerves’ motor fibers. Needle electromyography revealed signs of moderate active denervation, fasciculation potentials, and reinnervation signs at the cervical segments, is typical for anterior horn dysfunction. Cervical spine MRI showed signs of osteochondrosis and deforming spondylosis, the spinal cord was unremarkable. The diagnosis of possible ALS was made. After a year, she came to our department. Neurologic examination revealed the raised tonicity on the neck muscles. MRI revealed spinal cord T2-hyperintensity at the C2-C5 levels in anterior horns, more severe at the left side (Fig. 2). Needle electromyography revealed signs typical for anterior horn dysfunction only at the cervical segments. Thus cervical spondylotic myelopathy was diagnosed. Conclusion It is worth remembering that the cervical spondylotic myelopathy is clinically heterogenous and can mimic amyotrophic lateral sclerosis. It seemed to us that for the avoidance of diagnostic pitfalls a follow-up study for such patients should include not only needle electromyography but also spinal cord MRI.