Gabapentin is a first line medication and fentanyl is second line medication in neuropathic pain. But, there is no head to head study on the efficacy of those medication in neuropathic pain.

The hypothesis of this study is that the efficacy of the transdermal fentanyl matrix is not inferior to the gabapentin in neuropathic pain.

Inclusion Criteria:

• patients are 20 years of age or older
• patients had chronic pain for more than 3 months and average pain score for last 3 days is not less than 4 (NRS)
• neuropathic pain caused by the spinal stenosis (radiating pain, motor or sensory change
• positive MRI finding or radiculopathy was confirmed by the EMG/NCS or not less than 12 points in the S-LANSS score assessment
• patients who can make out the questionnaire
• patients have agreed with the informed consent

Exclusion Criteria:

• patients who have experience with gabapentin, pregabalin, fentanyl matrix, long-acting strong opioid (CR oxycodone, SR morphine)
• patients who have other causes of neuropathy such as hypothyroidism, Vit B12 deficiency, connective tissue disease, etc.
• patients who have other disease which causes more pain compared with neuropathic pain
• patients with a history of drug or alcohol abuse
• patients who are pregnant or have the possibility of pregnancy
• patients who are unable to use a transdermal system due to skin disease
• patients with a serious mental disease
• patients with a history of hypersensitivity to opioid analgesics
• patients with a chronic pulmonary disease or respiratory depression
• patients combined with industrial accidents or traffic accidents
• at investigator's discretion, any condition where a subject cannot take part in the clinical study on the ground of warning, cautions, and prohibition in study investigator's brochure