Interventional pain management

[1] Medicare Payment Advisory Commission (MedPAC) defined interventional techniques as, "minimally invasive procedures including, percutaneous precision needle placement, with placement of drugs in targeted areas or ablation of targeted nerves; and some surgical techniques such as laser or endoscopic diskectomy, intrathecal infusion pumps and spinal cord stimulators, for the diagnosis and management of chronic, persistent or intractable pain".

[2] Minimally invasive interventions such as facet joint injections, nerve blocks (interrupting the flow of pain signals along specific nervous system pathways), neuroaugmentation (including spinal cord stimulation and peripheral nerve stimulation), vertebroplasty, kyphoplasty, nucleoplasty, endoscopic discectomy, and implantable drug delivery systems are utilized in managing subacute or chronic pain.

[3][4] Early efforts at interventional pain management date back to the origins of regional analgesia and nerve blocks, and gradually evolved into a distinct specialty.

[4] Radiotherapy is used when drug treatment is failing to control the pain of a growing tumor, such as in bone metastasis (most commonly), penetration of soft tissue, or compression of sensory nerves.

Often, low doses are adequate to produce analgesia, thought to be due to reduction in pressure or, possibly, interference with the tumor's production of pain-promoting chemicals.

[8] A neurolytic block is the deliberate injury of a nerve by the application of chemicals (in which case the procedure is called "neurolysis") or physical agents such as freezing or heating ("neurotomy").

Neurectomy involves cutting a nerve, and is (rarely) used in patients with short life expectancy who are unsuitable for drug therapy due to ineffectiveness or intolerance.

[11] Cordotomy involves cutting into the spinothalamic tracts, which run up the front/side (anterolateral) quadrant of the spinal cord, carrying heat and pain signals to the brain.

One study[13] of seventeen patients with intractable cancer pain found that thirteen were virtually painless and only four required opioid analgesics on release from hospital after the intervention.