Cooled and traditional thermal radiofrequency ablation of genicular nerves in patients with chronic knee pain: a comparative outcomes analysis.

INTRODUCTION: Genicular nerve radiofrequency ablation (GNRFA) is a minimally invasive intervention for patients with chronic knee pain (CKP) not responding to conservative treatments. Few investigations have compared treatment outcomes of cooled-RFA (c-RFA) and thermal-RFA (t-RFA), two common approaches of GNRFA. This study aims to investigate and compare outcomes, including probability of treatment success, between c-RFA and t-RFA in patients with CKP. METHODS: This retrospective cohort study analyzed a total of 208 propensity score matched patients, including 104 patients who received c-RFA and 104 patients who received t-RFA. The primary outcome was probability of pain relief after the procedure, defined as reduction in Numeric Rating Scale (NRS) pain score of 2 or greater. The secondary outcomes were degree of NRS pain score reductions, duration of relief, and the probability of patients receiving TKA within 1 year of treatment. RESULTS: T-RFA was associated with a higher probability of pain relief within 1, 3, and 6 months after procedure when compared with c-RFA. Probabilities of pain relief from t-RFA and c-RFA were 62% (95% CI 51% to 71%) and 43% (95% CI 34% to 53%; p=0.01) within 1 month, 78% (95% CI 68% to 85%) and 55% (95% CI 45% to 64%; p<0.001) within 3 months, and 79% (95% CI 70% to 86%) and 59% (95% CI 49% to 68%; p<0.01) within 6 months, respectively. t-RFA was also associated with greater mean NRS pain score reduction at 1 month after procedure: -4.71 (95% CI -5.3 to -4.1) when compared with -3.59 (95% CI -4.3 to -2.9; p=0.02) from c-RFA. T-RFA and c-RFA were comparable in pain score reduction at 3, 6, 9 and 12 months after procedure. Both groups demonstrated comparable duration of relief and probability of patients receiving TKA within 1 year. DISCUSSION: Both t-RFA and c-RFA effectively reduced NRS pain scores in most patients with CKP within the 1 year follow-up period. Genicular nerve t-RFA was associated with a higher probability of treatment success and a greater degree of pain relief at 1 month after the procedure when compared with c-RFA in propensity score matched patients with CKP.

Intravenous Ketamine Infusion for Complex Regional Pain Syndrome: Survey, Consensus, and a Reference Protocol.

OBJECTIVE: To find and reach a consensus on the usage of ketamine in the treatment of complex regional pain syndrome and to determine a reference protocol for future studies. DESIGN: Three hundred fifty-one medical professionals participated in our survey on practice procedures, with 104 respondents providing information on their usage of ketamine for treating the pain associated with complex regional pain syndrome. Respondents answered questions about inpatient treatment, outpatient treatment, children vs adults, safety, and basic demographic information. An expert group then met to reach a consensus for a reference protocol. RESULTS: There is a difference in how inpatients are treated compared with outpatients, making it necessary to have two different reference protocols. The duration of pain relief varied from one to 10 days to one to six months, with a correlation between the duration of pain relief and total infusion hours per round. CONCLUSIONS: The consensus reference protocols are made up of nine recommended topics. Reference protocols need to be validated by extensive research before guidelines can be created.

Spinal Cord Stimulation 50 Years Later: Clinical Outcomes of Spinal Cord Stimulation Based on Randomized Clinical Trials-A Systematic Review.

To assess the efficacy of spinal cord stimulation (SCS) for each indication, one must critically assess each specific clinical outcome to identify outcomes that benefit from SCS therapy. To date, a comprehensive review of clinically relevant outcome-specific evidence regarding SCS has not been published. We aimed to assess all randomized controlled trials from the world literature for the purpose of evaluating the clinical outcome-specific efficacy of SCS for the following outcomes: perceived pain relief or change pain score, quality of life, functional status, psychological impact, analgesic medication utilization, patient satisfaction, and health care cost and utilization. Interventions were SCS, without limitation to the type of controls or the type of SCS in the active arms. For each study analyzed, a quality assessment was performed using a validated scale that assesses reporting, external validity, bias, confounding, and power. Each outcome was assessed specific to its indication, and the primary measure of each abovementioned outcome was a summary of the level of evidence. Twenty-one randomized controlled trials were analyzed (7 for trunk and limb pain, inclusive of failed back surgery syndrome; 8 for refractory angina pectoris; 1 for cardiac X syndrome; 3 for critical limb ischemia; 2 for complex regional pain syndrome; and 2 for painful diabetic neuropathy). Evidence assessments for each outcome for each indication were depicted in tabular format. Outcome-specific evidence scores were established for each of the abovementioned indications, providing both physicians and patients with a summary of evidence to assist in choosing the optimal evidence-based intervention. The evidence presented herein has broad applicability as it encompasses a breadth of patient populations, variations of SCS therapy, and comparable controls that, together, reflect comprehensive clinical decision making.