Long-term Inhibition of Soleus H-reflex with Epidural Adhesiolysis and Pulsed Radiofrequency in Lumbosacral Neuropathic Pain.

INTRODUCTION: Scientific data about neurophysiological changes subsequent to pulsed radiofrequency (PRF) are still lacking. The goal of this study was to evaluate sural nerve conduction and Hoffmann reflex (H-reflex) in soleus muscle following adhesiolysis and PRF in patients with unilateral chronic lumbosacral L5-S1 neuropathic radiating pain. METHODS: Seventeen patients received two cycles of 240 seconds high-voltage PRF and epidural adhesiolysis. Sural nerve action potential (SNAP) and the ratio of maximum H-reflex to maximum M response (H/M ratio) as well as pain scores were collected in both lower limbs before, immediately following, and 1 month after the treatment. RESULTS: At follow-up, a significant reduction in numeric rating scale (NRS) and Douleur Neuropathique 4 Questions (DN4) scores was observed in 53% of patients reporting pain improvement of ≥ 30% over baseline. The H/M ratio was decreased in the affected limb following PRF (P = 0.01) and 1 month after the treatment (P = 0.04). A direct correlation was observed between H/M ratio variation and NRS score at follow-up in the treated limb (P = 0.04). No significant difference in sural nerve latency, amplitude, and velocity was detected between affected and normal side after treatment and at follow-up. CONCLUSIONS: Epidural adhesiolysis and PRF of the dorsal root ganglion seem to significantly affect spinal reflexes in patients with lumbosacral neuropathic radiating pain.

Electrocatheter-mediated High-voltage Pulsed Radiofrequency of the Dorsal Root Ganglion in the Treatment of Chronic Lumbosacral Neuropathic Pain: A Randomized Controlled Study.

OBJECTIVES: Despite the interest in scientific community, there is still poor evidence about pulsed radiofrequency (PRF) efficacy in the treatment of neuropathic pain. In order to determine whether high-voltage PRF and epidural adhesiolysis (PRF-EA) showed better results than epidural adhesiolysis alone (EA), a randomized, double-blind, comparative-effectiveness study was conducted in patients with chronic lumbosacral radiating pain and neuropathic features. MATERIALS AND METHODS: A total of 41 patients were randomly allocated to 2 groups. Twenty-one patients were randomized to receive 2 cycles of 240 seconds high-voltage PRF followed by the injection of local anesthetics, hyaluronidase, and betamethasone, whereas 20 patients underwent sham stimulation followed by adhesiolysis. The treatment was delivered at the affected lumbosacral roots and patients, treating physicians and assessors were blinded to intervention. RESULTS: A significant reduction of radiating pain was observed in mean Numeric Rating Scale score at follow-up. A change of -3.43 versus -1.75 (P=0.031) after 1 month and -3.34 versus -0.80 (P=0.005) after 6 months was reported in patients undergoing PRF-EA in comparison with EA, respectively. After 1 month, 57% of patients in the PRF-EA group experienced a pain reduction of ≥50% versus only 25% of patients allocated to EA (P=0.037). Improvement decreased to 48% in the PRF-EA group whereas only 10% of EA reported significant pain relief after 6 months (P=0.008). DISCUSSION: High-voltage PRF of dorsal root ganglion delivered through multifunctional electrode provided significant pain relief and may be considered a valuable treatment in chronic lumbosacral radicular pain with neuropathic features.

The appropriate management of persisting pain after spine surgery: a European panel study with recommendations based on the RAND/UCLA method.

PURPOSE: Management of patients with persisting pain after spine surgery (PPSS) shows significant variability, and there is limited evidence from clinical studies to support treatment choice in daily practice. This study aimed to develop patient-specific recommendations on the management of PPSS. METHODS: Using the RAND/UCLA appropriateness method (RUAM), an international panel of 6 neurosurgeons, 6 pain specialists, and 6 orthopaedic surgeons assessed the appropriateness of 4 treatment options (conservative, minimally invasive, neurostimulation, and re-operation) for 210 clinical scenarios. These scenarios were unique combinations of patient characteristics considered relevant to treatment choice. Appropriateness had to be expressed on a 9-point scale (1 = extremely inappropriate, 9 = extremely appropriate). A treatment was considered appropriate if the median score was ≥ 7 in the absence of disagreement (≥ 1/3 of ratings in each of the opposite sections 1-3 and 7-9). RESULTS: Appropriateness outcomes showed clear and specific patterns. In 48% of the scenarios, exclusively one of the 4 treatments was appropriate. Conservative treatment was usually considered appropriate for patients without clear anatomic abnormalities and for those with new pain differing from the original symptoms. Neurostimulation was considered appropriate in the case of (predominant) neuropathic leg pain in the absence of conditions that may require surgical intervention. Re-operation could be considered for patients with recurrent disc, spinal/foraminal stenosis, or spinal instability. CONCLUSIONS: Using the RUAM, an international multidisciplinary panel established criteria for appropriate treatment choice in patients with PPSS. These may be helpful to educate physicians and to improve consistency and quality of care. These slides can be retrieved under Electronic Supplementary Material.

Combined epidural morphine and bupivacaine in the treatment of lumbosacral radicular neuropathic pain: a noncontrolled prospective study.

OBJECTIVE: The aim of this study was to investigate the therapeutic effectiveness of epidural morphine and bupivacaine in patients with chronic lumbosacral radicular neuropathic pain after the cessation of treatment. METHODS: Twenty-two patients with chronic lumbosacral pain with neuropathic features were enrolled. An indwelling catheter was placed into the epidural space, and each patient received an epidural injection of morphine chlorhydrate and bupivacaine up to three times a day. The medication was administered for 4 weeks. The pain intensity score on a 0-10 numeric rating scale (NRS), the total pain rating index rank (PRIr-T), and its coefficients were evaluated before treatment and 1 month after catheter removal. P-value <0.05 was considered statistically significant. RESULTS: NRS and PRIr-T were significantly reduced at follow-up (P=0.001 and P=0.03, respectively), whereas the parallel evolution of the two scores (r=0.75 and P<0.001, respectively) confirmed significant pain relief lasting up to 1 month after treatment cessation. None of the four pain rating coefficients was significantly modified compared to the others in either responders or nonresponders. Successful clinical outcome (pain reduction >30% in NRS) was reached and maintained in half of the patients at follow-up. CONCLUSION: Combined epidural morphine and bupivacaine seems to be effective in the treatment of neuropathic pain.

Effectiveness of pulsed radiofrequency with multifunctional epidural electrode in chronic lumbosacral radicular pain with neuropathic features.

BACKGROUND: Lumbosacral radicular pain is a common clinical finding with a statistical prevalence ranging from 9.9% to 25% in the general population. OBJECTIVE: To investigate the effectiveness of dorsal root ganglion pulsed radiofrequency (PRF) in patients with chronic lumbosacral radicular pain and neuropathic features. STUDY DESIGN: Prospective case series clinical outcome study. METHODS: We evaluated 34 patients with lumbosacral neuropathic pain who underwent PRF at the corresponding level of radicular symptoms distribution (ranging from L3 to S1). Each patient suffered a single leg-radiating pain with probable neuropathic features (assessed with clinical grading) lasting for > 6 months and unresponsive to previous treatments. A multifunctional PASHA-electrode® was introduced with trans-sacral access through a hollow needle, placed under fluoroscopic guidance into the lumbosacral epidural space and its active tip moved close to the dorsal root ganglion responsible of the clinical symptoms. After connecting the electrode to a generator, stimulation tests were performed and PRF was started and applied for 240 seconds at a frequency of 2Hz, amplitude of 45 V and a tip temperature between 40 - 42°C. If the pain involved more than a single nerve root, the electrode was placed at a different segment and the procedure repeated. Outcome measures included the pain intensity score on a 0 - 10 numeric rating scale (NRS) and the Italian Pain Questionnaire (QUID) at pre-treatment, one and 6 months post-treatment. P values < 0.05 were considered statistically significant. RESULTS: In comparison with pre-treatment, a significant reduction in pain score was observed in mean NRS either at one and 6 months (P < 0.001). The QUID - Pain Rating Index rank displayed a parallel trend at the first (P < 0.001) and last follow-up (P = 0.01). Moreover, a direct correlation between the 2 scales occurred, showing a parallel score decreasing (P < 0.001). Eighteen (52.9%) and 17 (50%) of 34 patients showed pain reduction in NRS > 2 points and > 30%, at one and 6 months, respectively. LIMITATIONS: The non-controlled design of the study, the patients were heterogeneous, the small number of patients, and the duration of follow-up was limited to 6 months. CONCLUSIONS: PRF of dorsal root ganglion performed with a multifunctional electrode for > 240 seconds appears to be safe and might be more effective than the classic 120 seconds needle-mediated approach. Therefore, it may be considered as a valuable tool for the treatment of lumbosacral radicular pain with neuropathic features.

Rare adverse effect of spinal cord stimulation: micturition inhibition.

OBJECTIVES: In current medical literature, most of the reported complications of spinal cord stimulation concern technical problems, such as lead malfunction, migration, breakage, or internal pulse generator dysfunction, whereas reports about the side effects on internal organ function caused by spinal cord stimulation are rare. METHODS: In this clinical report, we describe uncommon side effects owing to spinal cord stimulation in a patient with chronic neuropathic pain. Our patient developed unexpected urinary retention during electrical epidural stimulation. RESULTS AND DISCUSSION: This case report highlights the incomplete knowledge about the mechanism of action of spinal cord stimulation and its influence on the interactions between the autonomic nervous system and voluntary control of urinary function. The complete recovery of bladder function after the interruption of stimulation suggests that electrical stimulation caused the adverse effects in this clinical case.

Rare Side-effects during Spinal Cord Stimulation: Gastrointestinal Symptoms.

In current medical literature, most reported complications during spinal cord stimulation (SCS) concern technical problems, such as malfunction, migration or breakage of the lead, or internal pulse generator dysfunction, while reports about side-effects caused by SCS are rare. In this clinical report, we describe uncommon and unexplained gastrointestinal (GI) side-effects of constipation, abdominal pain, and distension during SCS in a patient suffering for chronic neuropathic pain caused by failed back surgery syndrome. These GI symptoms disappeared after suspension of SCS and were reduced if the stimulation settings were reduced below paresthesia threshold. The symptoms experienced by our patient could be related to a functional and reversible block of parasympathetic outflow in the GI system since SCS may involve not only dorsal horn structures but also somatic and visceral sensory afferents to these structures in an unpredictable way.