頚椎症性脊髄症における脊髄障害性疼痛症候群

抄録

　Cervical spondylotic myelopathy (CSM) is a disease showing various symptoms such as numbness of upper and lower extremities, disturbed fine motor skills, and gait disturbance due to spinal cord compression. CSM causes high degree of ADL (activities of daily living) disturbance due to these symptoms. Some patients show allodynia or hyperalgesia in upper and lower extremities. However, neuropathic pain in patients with CSM has not been paid attention as much as pain following spinal cord injury. The purpose of the current study was to determine the incidence of severe allodynia or hyperalgesia in upper and lower extremities in patients with CSM, and to clarify the characteristics of these patients. This study was approved by our IRB. A questionnaire was sent to 317 patients with CSM who were surgically treated in our hospital during the past 20 years. Data from 139 cases were available for analysis. Subjects were divided into two groups: Severe Pain group (NRS (numerical rating scale) of allodynia or hyperalgesia in upper and lower extremities was 5 and more than 5) and Light Pain group (NRS was less than 5). Age, gender, QOL (EQ-5D and SF-36), JOACMEQ (myelopathy evaluation questionnaire), McGill Pain Score, and the Neuropathic Pain Symptom Inventory were compared between these two groups. Non-parametric tests were used for statistical analysis. There were 57 cases (41%) in the Severe Pain group and 82 cases (59%) in the Light Pain group. There were no differences in age and gender between two groups. However, the EQ-5D was 0.560 ± 0.152 in the Severe Pain group and 0.698 ± 0.179 in the Light Pain group (p<0.001). On the SF-36, all 8 items showed lower scores in the Severe Pain group compared to the Light Pain group (p<0.005〜0.001). On the JOACMEQ, all 5 items showed worse scores in the Severe Pain group compared to the Light Pain group (p<0.05〜0.001). The McGill Pain Score was 8.10 ± 7.79 in the Severe Pain group and 2.47 ± 5.23 in the Light Pain group (p<0.001). The total score of the Neuropathic Pain Symptom Inventory was 22.92 ± 23.72 in the Severe Pain group and 8.03 ± 14.10 in the Light Pain group (p<0.001). There were 41% of patients showing severe allodynia or hyperalgesia in upper and lower extremities in CSM. These patients showed lower QOL and severe myelopathy. We should pay attention to allodynia or hyperalgesia in upper and lower extremities in patients with CSM.