Minimally-invasive percutaneous treatments for low back pain and leg pain: a randomized controlled study of thermal...

Minimally invasive techniques have recently been developed as alternative treatments to surgical interventions, especially for small or contained herniated disc.

Aim of our study is to assess the efficacy of the mechanical percutaneous disc decompression (PDD) in comparison with the percutaneous radiofrequency targeted disc decompression (TDD).

We conducted a single-center noninferiority trial in which patients who had low back pain with radicular leg pain (RLP) from a contained herniated disc were randomly assigned in a 1:1 ratio to undergo either PDD or TDD.

From January 2016 to January 2017 a total of 327 patients were assessed for eligibility of whom 200 underwent randomization in the trial; 100 patients underwent the PDD and 100 underwent the TDD.

The primary outcome measure was the proportion of patients who reported >50% reduction in Numeric Rating Scale (NRS) leg pain score. Secondary outcome measure included the proportion of patients who reported >30% improvement in Oswestry Disability Index (ODI) score.

Outcomes of this trial were measured with the use of patient-reported data obtained from validated questionnaires to assess the low back pain with RLP before intervention and at 6 and 12 months after interventions. MRI was performed before intervention and at 6 and 12 months after interventions. In addition to NRS and ODI scores, we collected the following data: age, gender, length of hospitalizations and return to work rate.

When using an intention to treat analysis with those lost to follow-up and requiring a second procedure counting as failures, there were no statistically significant difference between the two treatment groups in the primary and secondary outcomes at 6 months: >50% reduction in NRS leg pain (PDD vs. TDD)=67% versus 65%; >30% ODI improvement (PDD vs. TDD)=57% versus 55%. Similarly, there were no statistically significant differences between groups in outcomes at 12 months: >50% reduction in NRS leg pain (PDD vs. TDD)=51% (95% CI 41%-60%) versus 40% (95% CI: 30%-49%); >30% ODI improvement (PDD vs. TDD)=42% (95% CI 32%-51%) versus 30% (95% CI: 21%-39%). A nonintention to treat analysis which discounted those lost to follow-up showed the only statistically significant finding was the percentage of those reporting >30% ODI at the 12 month follow-up time, favoring the PDD group: (PDD vs. TDD)=58% (95% CI 46%-69%) versus 42% (95% CI: 22%-43%).

PDD and TDD are comparable treatments for patients presenting with low back pain with RLP unresponsive to medical therapy caused by contained disc herniations.