Paraplegia secondary to progressive necrotic myelopathy in a patient with an implanted morphine pump.

We present an individual with chronic low back pain who was treated with an implanted morphine pump, which provided very good pain relief for 16 mos. However, the patient developed acute paraplegia secondary to progressive necrotic myelopathy, a rare form of transverse myelitis. The cause of this patient's neurologic deficit was unclear. Three months after the onset of paralysis, a trial of discontinuation of the intrathecal morphine was performed to exclude the morphine as a reversible cause of paralysis. Within 24 hrs after his pump was depleted, his pain became significantly worse. He was maintained on oral opioids for 6 mos, and his pain was only partly controlled, with a daily average visual analog scale score of 7/10. There was no improvement in his neurologic status after stopping the intrathecal morphine therapy, and several consecutive magnetic resonance images of the spine demonstrated radiologic progression of spinal cord involvement. The patient developed classic opioid side effects of excessive somnolence and constipation. Intrathecal morphine therapy was re-instituted, and the patient reported a significant decrease of his pain, an improvement in quality of life, and no complications related to pump functioning.