Intrathecal morphine for postoperative pain control after laminoplasty in patients with cervical spondylotic myelopathy.

Abstract

To examine the clinical efficacy of intrathecal morphine as postoperative analgesia for cervical laminoplasty. Patients who undergo posterior cervical spinal surgery frequently experience significant postoperative pain. Postoperative pain contributes to patient morbidity because of decreasing early voluntary mobilization and delayed rehabilitation. Intrathecal morphine is known to be a simple and effective analgesia. However, the effectiveness of intrathecal morphine for cervical spinal surgery has not yet been reported. Seventy-eight patients with cervical spondylotic myelopathy were divided into two groups prospectively, a diclofenac suppository (DS) group who received 50mg diclofenac suppository at the end of the surgery, and an intrathecal morphine (ITM) group who were preoperatively administered 0.3mg of morphine chloride, intrathecally, via a lumbar puncture. All patients underwent double-door laminoplasty of C3-6 or C3-7 level. Visual analog scale (VAS) of cervical pain, self-rating pain impression, supplemental analgesic usage, and complication rate were evaluated until the seventh postoperative day. Thirty-one patients in the DS group and 32 patients in the ITM group were finally assessed. No baseline variable differences between the two groups were observed. The VAS was significantly lower in the ITM group at 4h and 24h until the seventh postoperative day. Self-rating pain impression was significantly better in the ITM group. No significant difference was observed in complication rate. Intrathecal morphine was an effective and safe analgesic method for cervical laminoplasty in patients with cervical spondylotic myelopathy.