Motor Neuron Disease in a Patient With Cervical Spondylotic Myelopathy: Too Much Bad Luck

Cervical spondylotic myelopathy (CSM) and amyotrophic lateral sclerosis (ALS) share some clinical findings. Hence, motor neuron disease (MND) should be considered in the differential diagnosis of patients presenting with signs and symptoms of CSM. This unique case demonstrates the coexistence of both conditions in the same patient. The author reports the case of a 74-year-old male who initially underwent posterior cervical decompression and instrumented fusion for cervical myelopathy. He demonstrated postoperative improvement followed subsequently by unexplained neurological deterioration. A repeat MRI showed adequate decompression of the cervical cord and persistence of T2 hyperintense signal in the spinal cord. Based on the presence of signs and symptoms of lower motor neuron disease, electromyography (EMG) was performed demonstrating findings of MND. The presence of MND in a patient with CSM is unique and can be difficult to diagnose based on overlapping symptoms. This case highlights the importance of EMG and the vigilance that spine surgeons need to display to identify ALS or other MND, despite the presence of ongoing cervical myelopathy. In cases where patients show discordant symptoms, further studies should be performed.