Pulsed Radiofrequency of Non-neural Tissues

This is an open-access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http:// creativecommons.org/licenses/by-nc/3.0/), which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. Pulsed radiofrequency (PRF) has been used to manage a wide spectrum of chronic pain modalities because it produces fewer histopathological changes than conventional RF and takes advantage of a significant reduction in complications or side effects [1]. Many reports have indicated that PRF improves chronic pain when applied to various neural tissues, including the dorsal root ganglion [2], cra-nial nerves [3], medial branches of spinal nerves [4], and other peripheral nerves [5]. Unlike neural tissues, few reports have investigated the effect of applying PRF to non-neural tissues. In the latest issue of The Korean Journal of Pain, Fukui et al. [6] reported a clinical study that compared the effects of intradiscal PRF and electrothermal therapy in 31 patients with lumbar discogenic pain. In this trial, intra-discal PRF was as effective as electrothermal therapy. At up to the 6 month follow-up, the mean numeric rating scale and Roland-Morris Disability Questionnaire score improved significantly after intradiscal PRF was applied for 15 min under conditions 5 × 50 ms/s and 60 V. Three other pilot studies, which included no control group, showed the effectiveness of intradiscal PRF for discogenic pain [7-9]. However, we are unaware of the long-term effectiveness and safety of intradiscal PRF. Further randomized controlled studies with long-term follow-up durations are crucial to verify the efficacy and safety of intradiscal PRF. The editor found a retrospective study and two case reports by PubMed search regarding the effect of in-tra-articular application of PRF. Karaman et al. [10] reviewed 31 patients with osteoarthritis of the knee who received intra-articular PRF retrospectively. After applying PRF at 42 o C and 2 Hz for 15 minutes, the mean initial visual analog scale scores of patients (6.1 ± 0.9) decreased to 3.9 ± 1.9 cm and 4.1 ± 1.9 cm at the 1-and 6-month follow-ups respectively. Sluijter et al. [11] reported six cases of patients with intractable arthrogenic pain who were treated with intra-articular PRF. In this case series, PRF was applied by placing an electrode into joint spaces, including the cervical facet joint, the knee joint, the sacroil-iac joint, the radiocarpal joint, the shoulder joint, and the atlanto-axial joint. All participants experienced a significant reduction in pain or a …