Pharmacological Interventions for Neuropathic Pain Associated with Compressive Myelopathy

Neuropathic pain following spinal cord injury (SCI) is a common problem in patients with SCI, which influences the quality of life of such patients. However, in our experiments of treatments for patients with compressive myelopathy, neuropathic pain was identified in patients with not only SCI, but also those with compressive myelopathy. The objective of this study was the evaluation of pharmacological interventions for neuropathic pain associated with compressive myelopathy (NePCM). Forty-five consecutive patients with NePCM who underwent pharmacological interventions from 2005 to 2016 were included in the study. Patient records were analyzed retrospectively. Evaluated factors were visual analog scale (VAS) and grid score (GS), which were used for quantification of pain. Effective pharmacological interventions were identified when VAS or GS decreased more than 10 points after treatments. The patients’ diagnoses were as follows: cervical or thoracic ossification of posterior longitude ligaments in 17 patients, cervical spondylotic myelopathy in 12 patients, disc herniation in 3 patients, and other diagnoses in 13 patients. All patients received decompression surgery with or without spinal fusion except 7 patients. Cervical lesions were in 32 patients, thoracic lesions were in 11 patients, and both cervical and thoracic lesions were in 2 patients. Pain distribution was at-level in 10 patients, below-level in 23 patients, and both at-level and below-level in 12 patients. Effective interventions were anticonvulsants for 19 patients, antidepressants for 10 patients, and other interventions for 3 patients. The effective anticonvulsants were pregabalin for 9 patients, gabapentin for 6 patients, and chronazepam for 5 patients. The effective antidepressants were duloxetine for 7 patients. However, 15 patients did not respond to any medications. Anticonvulsants and antidepressants are likely to be effective for NePCM, however, some patients do not respond to these interventions. Therefore, advanced treatments have to be developed for NePCM.