Department of Orthopaedic Surgery, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan.
Department of Orthopaedic Surgery, Nihon University, Tokyo, Japan; and.
J Clin Neurophysiol. 2024 May 1;41(4):351-356. doi: 10.1097/WNP.0000000000000990. Epub 2023 Mar 8.
Thoracic myelopathy is a rare condition whose diagnosis is often missed or delayed. This study aimed to differentiate between cervical and thoracic myelopathy using motor-evoked potential testing.
The authors included 835 patients with compressive cervical myelopathy and 94 patients with compressive thoracic myelopathy. Myelopathy using motor-evoked potentials were recorded from the bilateral abductor digiti minimi and abductor hallucis muscles through transcranial magnetic stimulation. The peripheral conduction time was measured through electrical stimulation of the ulnar and tibial nerves; moreover, the central motor conduction time (CMCT) was calculated by subtracting the peripheral conduction time from the myelopathy using motor-evoked potential latency.
The most accurate differentiation between compressive cervical myelopathy and compressive thoracic myelopathy was achieved by the CMCT ratios (CMCT-ADM:CMCT-AH; cutoff value of 0.490, sensitivity of 83.0%, and specificity of 80.5%). After excluding patients with compressive cervical myelopathy who had spinal cord compression at C6-7, the cutoff value was 0.490, with a sensitivity of 83.0% and specificity of 87.3%.
Determining the CMCT ratio (cutoff value of 0.490) through motor-evoked potential testing could facilitate differentiation between compressive cervical myelopathy and compressive thoracic myelopathy.
胸髓病是一种罕见的疾病，其诊断常常被忽视或延迟。本研究旨在通过运动诱发电位检查来区分颈髓病和胸髓病。
作者纳入了 835 例压迫性颈髓病患者和 94 例压迫性胸髓病患者。通过经颅磁刺激记录双侧趾短屈肌和踇展肌的运动诱发电位。通过对尺神经和胫神经的电刺激测量周围传导时间；此外，通过从运动诱发电位潜伏期中减去周围传导时间来计算中央运动传导时间（CMCT）。
CMCT 比值（CMCT-ADM：CMCT-AH；截止值为 0.490，敏感性为 83.0%，特异性为 80.5%）是区分压迫性颈髓病和压迫性胸髓病最准确的方法。排除 C6-7 脊髓受压的压迫性颈髓病患者后，截止值为 0.490，敏感性为 83.0%，特异性为 87.3%。
通过运动诱发电位检查确定 CMCT 比值（截止值为 0.490）有助于区分压迫性颈髓病和压迫性胸髓病。
