SMART trial shows nerve ablation “well-tolerated and effective”

Relievant Intracept

Both surgical and conservative methods of treating chronic low back pain have reported variable scientific and clinical outcomes. New prospective, double-blinded, randomised, sham-controlled trial results presented at the annual meeting of the International Society for the Advancement of Spinal Surgery (ISASS; 12–14 April, Boca Raton, USA) suggest that basivertebral nerve ablation could be an effective solution for this aetiology.

A team of researchers led by Jeffrey Fischgrund (Beaumont Hospital Royal Oak, Royal Oak, USA) evaluated the Intracept osseous nerve ablation system (Relievant Medsystems) as a treatment for chronic axial low back pain with collocated Modic changes. Using a minimally-invasive, transpedicular approach, the procedure aims to relieve pain associated with chronic low back pain by denervating the nociceptive (pain-sensing) nerves within the vertebral body via radiofrequency ablation.

“This procedure has the potential to provide relief to a large group of patients for whom there is no well-defined and routinely used therapy at present,” Fischgrund told Spinal News International.

The Surgical Multi-center Assessment of Radiofrequency Ablation for the Treatment of Vertebrogenic Back Pain (SMART) trial enrolled 225 patients in the USA and Germany across 15 centres presenting with isolated low back pain for at least six months, and in whom conservative treatment had failed.

One hundred and forty-seven patients received the Intracept treatment, with those remaining (n=78) receiving a sham procedure.

The observed improvement in Oswestry Disability Index (ODI) in the Intracept or treatment arm of 20.5 points was statistically superior to the sham arm (p=0.019). This improvement—which was maintained at two years follow-up—is twice the 10-point minimum clinically important difference for ODI as recognised in the published literature.

The authors also reported that an analysis of responder rates found that 75.6% of the Intracept arm patients demonstrated a greater than 10-point ODI improvement in their low back pain.

The safety of the device was demonstrated by a lack of unanticipated adverse device effects and a minimal, and between-arms comparable, rate of neurological events. Follow-up magnetic resonance imaging evaluations performed at six weeks and six months post-procedure found no evidence of any spinal cord abnormalities, a vascular necrosis or accelerated disc degeneration.

The study was limited by enrolment challenges, “due to the randomised sham (placebo) surgical arm,” Fischgrund noted. “However, the study was successfully completed, as per protocol.”

When asked for which physicians this procedure might offer a suitable treatment method, Fischgrund told Spinal News International, “Physicians who are comfortable performing percutaneous transpedicular procedures would be able to perform this procedure. Many spinal surgeons and spinal interventional physicians have such experience with pedicle screw placement and/or vertebral augmentation procedures.”

The authors concluded that their results demonstrate that the Intracept system is “safe, well-tolerated and effective for the treatment of low back pain in this patient population.”

Fischgrund told Spinal News International, “Low back pain is a multi-faceted and complex aetiology; the procedure has potential to address an important subset of such patients, specifically those in whom the pain is chronic, and presents in combination with Modic changes.”

The next step for this research will be further clinical confirmatory studies, Fischgrund told Spinal News International.

Providers of the system, he said, are planning on making the procedure available towards the end of 2017.