[A Case of Subacute Combined Degeneration Caused by Vitamin B₁₂ Deficiency in a Cervical Spondylosis Surgery Referral].

A 62-year-old man with a 1-year history of numbness of the extremities, clumsiness, and gait disorder was diagnosed with cervical spondylotic myelopathy at a neighboring clinic and referred to our institution for surgery. The patient had undergone a total gastrectomy 6 years previously. Flattening of the cervical cord, associated with diffuse cervical spondylosis and intramedullary intensity change, was observed on magnetic resonance imaging of the cervical spine. Neurological examination revealed decreased vibratory and position sense in all limbs, with posterior funiculus-based neurological symptoms. Blood biochemistry revealed decreased vitamin B₁₂(VB₁₂)levels and megaloblastic anemia. On the basis of these findings, the patient was diagnosed with subacute combined degeneration(SCD). The patient was treated with VB₁₂ for 3 months; the gait disorder resolved and the intramedullary intensity changes in the posterior column of the medulla oblongata, thoracicus, and spinal cord were no longer observed. SCD is a pathological condition in which recovery of neurological function may be achieved through early administration of VB₁₂. In some cases, it is difficult to differentiate between this condition and cervical spondylotic myelopathy because both diseases exhibit progressive spinal symptoms. The medical history and results of neurological evaluations of the patient are important for an accurate diagnosis, and should therefore not be overlooked.