Peripheral nerve field stimulation (PNFS) in chronic low back pain: a prospective multicenter study.

OBJECTIVES

The goal of this study was to evaluate the long-term efficacy and safety of peripheral nerve field stimulation (PNFS) for chronic low back pain (cLBP).

MATERIALS AND METHODS

In this prospective, multicenter observational study, 118 patients were admitted to 11 centers throughout Austria and Switzerland. After a screening visit, all patients underwent a trial stimulation period of at least seven days before implantation of the permanent system. Leads were placed in the subcutaneous tissues of the lower back directly in the region of greatest pain. One hundred five patients were implanted with a permanent stimulating system. Patients' evaluation of pain and functional levels were completed before implantation and one, three, and six months after implantation. Adverse events, medication usage, and coverage of the painful area and predictive value of transcutaneous electrical nerve stimulation (TENS) were monitored.

RESULTS

All pain and quality-of-life measures showed statistically significant improvement during the treatment period. These included the average pain visual analog scale, the Oswestry Disability Questionnaire, the Becks Depression Inventory, and the Short Form-12 item Health survey. Additionally, medication usage with opioids, nonsteroidal anti-inflammatory drugs, and anti-convulsants showed a highly significant reduction. Complications requiring surgical intervention were reported in 9.6% of the patients. The degree of coverage of painful areas seems to be an important criterion for efficacy of PNFS, whereas TENS is presumably no predictor.

CONCLUSIONS

This prospective, multicenter study confirms that PNFS is an effective therapy for the management of cLBP. Significant improvements in many aspects of the pain condition were measured, and complications were minimal.