Only about 1% of implanted drug delivery system patients (who are therefore at risk for inflammatory granuloma) actually develop the condition.
The term inflammatory granuloma describes the formation of an inflamed mass of tissue right where the catheter is inserted during the procedure.
Inflammatory granuloma occurs more frequently when the drug delivery system is implanted in the intrathecal space (a space that is located inside the layers of the spinal cord), as opposed to the epidural space (which is located on the outside).
Signs and Symptoms
Some of the early signs of inflammatory granuloma include loss of sensation and pain in the dermatome that corresponds to the level of the spinal cord where the catheter is inserted. Later signs include paralysis and bowel and/or bladder dysfunction. If your healthcare provider determines that you have inflammatory granuloma, she will likely stop the drug delivery immediately, and you may also need surgery.
According to Dr. Sudhir Diwan, director of the division of pain medicine at Weil-Cornell Medical College, inflammatory granuloma can present itself for up to six months after the catheter has been placed. But it also may take years before there are symptoms. Dr. Diwan says that inflammatory granuloma is related to the dosage or concentration of morphine delivered by the pump. He adds, “we like to place the catheter lower down, below the L-1 vertebra, as there is no spinal cord in that area, which minimizes injury.”
Prevention
Prevention of inflammatory granuloma may be accomplished by changing the medications delivered by the pump, using more than one area for catheter insertion and/or by not allowing dosages of morphine and hydromorphone to get too high.
Should You Have a Drug Pump Put In?
Drug pumps are generally a last resort type of treatment for chronic neck or back pain. So they work? Maybe, maybe not. It may depend on the type of pain you have. A 2014 article published in the Journal of Pain Research found that drug pumps implanted for the long-term relief of non-cancer pain were not well supported by evidence but that drug pumps that deliver the medication baclofen to help reduce spasticity (caused by spinal cord injury) were.
