Catheter Delivers Pain Drugs Into the Spine, Cutting Opioid Use in Six Patients

Six patients with back pain severe enough to resist everything else clinicians had tried reported an average pain score of 9.5 out of 10 before the procedure and zero immediately after it. Two of them stopped taking opioids entirely for the rest of their hospital stay. The results, presented Wednesday at the Society of NeuroInterventional Surgery's annual meeting in Seattle, come from a technique borrowed from stroke care and pointed at the spine.

The method is called bilateral targeted segmental artery lidocaine-dexamethasone infusion. A catheter enters through the femoral artery in the groin, is threaded up to the small segmental arteries that feed the suspected source of pain in the thoracolumbar spine, and delivers a local anesthetic and a steroid directly into that territory. The plumbing is standard interventional neuroradiology. The destination is not.

What the six patients experienced

Pain scores stayed low at three months, according to the abstract. Four of the six were able to take part in physical therapy afterward, which their pain had made impossible before — a detail that matters more than it sounds, since rehabilitation is the intervention with the strongest long-term evidence in chronic back pain and is precisely what severe pain locks patients out of.

"Neurointervention has transformed how we treat stroke, aneurysms and other diseases of the brain and spine. Now we're beginning to ask whether those same minimally invasive techniques can help patients living with severe pain," said Matias Costa, MD, the lead author, of the neurosurgery department at the University of Texas Medical Branch.

Costa was direct about the stage of the work: "While we're still in the early stages, these findings suggest endovascular therapy could one day play a role in reducing pain, improving function and decreasing reliance on opioids."

Six patients is a signal, not a finding

The numbers deserve the caution their authors gave them. This is a preliminary case series with no control group, no sham comparison, no blinding and no randomization, presented as a conference abstract rather than a peer-reviewed paper. Pain is among the outcomes most responsive to placebo and to the simple attention of an invasive procedure, and a drop from 9.5 to zero measured immediately after an anesthetic infusion partly reflects the anesthetic doing what anesthetics do.

The three-month durability is the more interesting number, because lidocaine does not last three months and dexamethasone does not either. If the effect is real and lasts, something else is happening — a break in a pain cycle, an interruption of sensitization — and that is a mechanism question no series of six patients can answer. SNIS said further studies are needed to determine efficacy.

Why an opioid-sparing option matters here

Low back pain is the single leading cause of disability worldwide, affecting 619 million people in 2020 by the World Health Organization's count, with cases projected to reach 843 million by 2050 as populations grow and age. It is also one of the most common reasons an American adult is handed an opioid prescription.

Federal guidance has been trying to unwind that for years. The CDC's 2022 clinical practice guideline recommends nonopioid therapies as preferred for subacute and chronic pain outside of cancer, palliative and end-of-life care, and tells clinicians to weigh opioids only when expected benefits for pain and function outweigh the risks. But telling clinicians what not to prescribe works poorly when the alternatives on the shelf do not control the patient's pain, and the patients most likely to receive long-term opioids are exactly the ones whose pain has already defeated physical therapy, injections and non-opioid drugs.

That is the gap this technique is aimed at. Whether it fills it is unknown; what it does is add a candidate to a category — procedural, non-systemic, potentially repeatable — where there have been few new entrants.

The addiction-medicine reading

Treatment for prescribed opioid dependence usually begins long after the prescribing decision that started it, and the people who end up needing it rarely arrived through recreational use. They arrived through pain that would not stop and a clinician with limited options. Anything that shrinks the pool of patients placed on long-term opioids in the first place is prevention in the most literal sense.

The caveat is that a procedure available at academic neurointerventional centers is not a public health intervention. Catheter-based spinal infusion requires an angiography suite, a trained neurointerventionalist, and an inpatient stay — a resource profile that will not reach rural or safety-net settings for years, if ever, and one that maps poorly onto the geography of the opioid crisis. Recent work has underscored how much even ordinary therapeutic prescribing carries risk: a University of Manchester cohort published this month found fentanyl carried more than triple the respiratory-depression risk of codeine among hospital inpatients treated for non-cancer pain.

The SNIS meeting, running July 20–24 at the Seattle Convention Center, brought the society's conference to the city for the first time. The pain abstract was one of several presentations there arguing that neurointerventional tools built for one problem may be repurposed for others. The argument is plausible. Six patients is where it starts, not where it is settled.