The Potential Role of SI00B and Brain Derived Neurotrophic Factor in Predicting Outcome From Using Pulsed Radiofrequency in Treatment of Patients With Lumbar Disc Prolapsed

Chronic lumbar radicular (CLR) pain is a term used to describe neuropathic pain symptoms in the distribution of a particular lumbar nerve root due to disc protrusion, spinal stenosis, facet hypertrophy, or fibrosis after previous surgery. The pathophysiology of CLR pain involves mechanical, inflammatory, and immunologic factors that affect the function of the dorsal root ganglion (DRG).1Treatment methods include oral pain medications, physical therapy, epidural steroid injection (ESI) and surgery. 2,3. Pulsed radiofrequency (PRF) was developed as a modification of the well-known radiofrequency ablation treatment. In conventional radiofrequency ablation, a high frequency alternating current is used to produce coagulative necrosis of the target nerve tissue without any selectivity for nociceptive fibers. However, in PRF, a current in short (20 msec) high voltage bursts is followed by silent phases (480 msec) which allow for heat dissemination, keeping the target tissue controlled below 42°C. 4,5 The mechanisms via which PRF causes analgesia are still not clearly understood, but laboratory experiments have highlighted some possible ways in which it might act, including its effects on neuropathic pain. Clinical use of PRF has been expanding, despite there being limited evidence of clinical efficacy in the form of randomized controlled trials (RCTs). 6 There have been few RCTs using PRF-DRG for radicular pain. Van Zundert et al performed an RCT in subjects with cervical radicular pain.7 Simopoulos et al did a pilot study on lumbar radicular pain, but the methodology included application of conventional radiofrequency over PRF in the study group and was not an efficacy trial. As such, the efficacy of PRF-DRG in CLR has never been determined. 8 Neuroplasticity or neuronal plasticity refers to the ability of the nervous system to do neuronal remodeling, formation of novel synapses and birth of new neurons. Neuronal plasticity is intimately linked to cellular responsivenes