Genicular Nerve Pulsed Dose Radiofrequency (PDRF) Compared to Intra-Articular and Genicular Nerve PDRF in Knee Osteoarthritis Pain: A Propensity Score-Matched Analysis

Genicular Nerve Ultrasound-Guided Cryoanalgesia for the Treatment of Chronic Knee Joint Pain: An Observational Retrospective Study

INTRODUCTION

Chronic knee pain caused by osteoarthritis (OA) is a prevalent source of disability in the adult population. Total knee arthroplasty (TKA) is an effective surgical treatment for advanced disease, but many patients continue to suffer from chronic post-surgical pain (CPSP). In recent years, minimally invasive techniques targeting peripheral nerves have been explored. Cryoanalgesia of the genicular nerves (GNCryo) is one such intervention that disrupts sensory input by applying extremely low temperatures to the target nerves, potentially leading to sustained pain relief without the need for neurodestructive heat lesions. This study aims to evaluate the effectiveness of ultrasound-guided GNCryo in patients with chronic knee pain due to primary OA or CPSP after TKA.

METHODS

This retrospective, single-center study included 90 patients who underwent GNCryo between September 2021 and February 2023. Inclusion criteria were patients over 18 years of age, symptomatic knee OA or CPSP after TKA, and a positive response (≥ 50% pain relief) to diagnostic genicular nerve blocks. Ultrasound guidance was used to optimize needle placement and reduce complications. Clinical outcomes were assessed at baseline and at 1, 3, 6, and 9 months post-procedure. Outcome measures included the Visual Analog Scale (VAS, 0-10) for pain intensity, the Western Ontario and McMaster Universities Arthritis Index (WOMAC, 0-100) for assessing pain, stiffness, and physical function related to OA, the Douleur Neuropathique en 4 Questions (DN4, 0-10) for neuropathic pain, and the EuroQol 5-Dimension (EQ-5D, 0-100) for quality of life.

RESULTS

Ninety patients completed the 9 months follow-up. The median VAS score decreased from 7.0 (6.0, 8.0) at baseline to 4.0 (3.0, 5.0) at 1 month, remained at 4.0 (3.0, 5.0) at 3 months, and increased slightly to 5.0 (4.0, 5.0) at 6 months and 5.0 (4.0, 6.0) at 9 months, yet pain relief remained lower than baseline. WOMAC scores decreased from 65 (55, 71) at baseline to 35 (30, 40) at 1 month and 35 (30, 40) at 3 months, increased to 40 (35, 50) at 6 months and 55 (45, 65) at 9 months. DN4 scores decreased from 7 (5, 8) at baseline to 4 (3, 4) at 1 month and 3 (2, 4) at 3 months, increased to 3.5 (3, 5) at 6 months and 5 (4, 6) at 9 months, yet remained lower than baseline. EQ-5D scores increased from 64.5 (47, 84) at baseline to 42 (32, 58) at 1 month, 43.5 (31, 59) at 3 months, 45.5 (35, 60) at 6 months, and 52 (41, 72) at 9 months.

CONCLUSIONS

Ultrasound-guided GNCryo is a promising minimally invasive treatment for chronic knee pain, providing pain relief and improved quality of life for up to 9 months. Although some outcomes showed a trend toward baseline over time, pain relief remained lower than baseline, consistent with potential nerve regeneration or recovery. Larger prospective, controlled trials are necessary to confirm these findings and to refine patient selection and technique optimization.

Genicular Nerve Radiofrequency Ablation for Chronic Knee Joint Pain Using a V-Shaped Active Tip Needle: A Single-Center Retrospective Observational Study

Background

Chronic knee pain from osteoarthritis (OA) affects a significant proportion of adults over 40. Total knee arthroplasty (TKA) remains the standard for advanced OA, yet up to 20% of patients experience chronic postsurgical pain (CPSP). Genicular nerve radiofrequency ablation (GNRFA) can alleviate pain in those unresponsive to conservative treatments or TKA. However, anatomical variability of the genicular nerves may limit treatment durability. This retrospective, single-center observational study investigated whether using a novel V-shaped active tip needle-which creates larger lesions-could improve outcomes.

Methods

Fifty patients with symptomatic knee OA or CPSP, who had a ≥50% reduction in pain after diagnostic genicular nerve blocks, underwent GNRFA with a V-shaped active tip needle between September 2020 and January 2022. Pain and function were assessed using the visual analogue scale (VAS) at rest and during movement, Western Ontario and McMaster Universities Arthritis Index (WOMAC), Douleur Neuropathique en 4 Questions (DN4), and EuroQol-5 Dimensions (EQ-5D) at baseline and 1, 3, 6, and 9 months post-procedure.

Results

By 6 months, 64% of patients showed ≥50% reduction in VAS pain scores, sustained at 9 months (p<0.0001). Median WOMAC scores improved from 62.0 at baseline to 40.0 at 6 months (p<0.0001). DN4 scores declined from a median of 4.0 at baseline to 2.0 at 6 months and 1.0 at 9 months (p<0.001). EQ-5D scores demonstrated significant enhancement in quality of life (p<0.01). Pain intensity differences at rest and during movement remained substantially improved at 9 months (p<0.0001).

Conclusion

GNRFA using a V-shaped active tip needle is a promising intervention for chronic knee pain, offering significant and sustained pain relief and functional improvement. Larger lesions created by the novel needle may overcome anatomical challenges, though further randomized studies are warranted to validate efficacy and safety.

Transforaminal Steroid Injection After Dorsal Root Ganglion Pulsed Radiofrequency (DRG-PRF): Impact on Pain Intensity and Disability

INTRODUCTION

Dorsal root ganglion pulsed radiofrequency (DRG-PRF) is frequently used for the treatment of chronic lumbar radicular pain with good outcomes in terms of pain management. Transforaminal epidural steroid injection (TFESI) is often administered immediately after DRG-PRF to increase the anti-inflammatory effects, but support for the synergic mechanism is lacking in the literature. The aim of this study was to investigate the potential role of TFESI immediately after DRG-PRF and its possible role on pain intensity and patient disability.

METHODS

A database of patients who underwent DRG-PRF with or without TFESI immediately after DRG-PRF was retrospectively analysed; propensity score matching was applied to the analysis to reduce possible bias. Pain intensity (numerical rating scale [NRS]) and Oswestry disability index (ODI) were recorded pre-operatively and at the 1- and 3-month follow-up in the two groups of patients.

RESULTS

A total of 252 patients were included in this retrospective analysis, 126 patients in the DRG-PRF + TFESI group and 126 patients in the DRG-PRF group after propensity score matching. Both groups displayed a significant reduction in pain intensity (NRS score reduction; p < 0.0001) and improvement in the ODI (p < 0.0001) from baseline at the 3-month follow-up. Interestingly, the use of TFESI after DRG-PRF was not associated with any clinical benefit as no difference in NRS and ODI was found between the two groups at the 1- and 3-month follow-ups.

CONCLUSIONS

Our study revealed a significant pain reduction and disability improvement after DRG-PRF in patients with lumbar radicular pain. Interestingly, no positive role of TFESI immediately after DRG-PRF was observed. These findings suggest that DRG-PRF provides substantial pain relief, and no added benefit is obtained with subsequent steroid injection. Future prospective studies with expanded follow-up periods are needed to confirm these findings.

Minimally invasive interventional procedures for osteoarthritis and inflammatory arthritis: A systematic review and meta-analysis

OBJECTIVE

to summarize the evidence on the efficacy of minimally invasive interventional procedures such as radiofrequency ablation (RFA) and transcatheter arterial embolization (TAE) in patients with osteoarthritis or inflammatory arthritis.

METHODS

a literature search was conducted in PubMed and Web of Science databases. Both randomized controlled trials (RCTs) and non-randomized studies of interventions (NRSI) were included. The results were organized according to the treated anatomical site: knee, hip, foot and ankle, shoulder, hand and wrist, sacroiliac joints. Data about treatment efficacy were extracted. The main outcome was change in pain intensity using the 0-10 visual analog scale (VAS) from baseline to 1 month. Additional timepoints at 3, 6 and 12 months were assessed. Change in functional status was evaluated. Pooled estimates were calculated as the mean difference (MD) and 95 % confidence interval relative to baseline. The meta-analyses of RCTs and NRSI were conducted separately.

RESULTS

of the 4599 retrieved articles, 164 were included in the review and, considering all the established timepoints, 111 (38 RCTs and 73 NRSI) were selected for the meta-analysis. Only one article described patients with inflammatory arthritis. In the meta-analysis of RCTs, one month after the procedure, MD in VAS was -3.98 (-4.41 to -3.55; k = 21) for knee RFA, and -3.18 (-3.96 to -2.39; k = 8) for sacroiliac joints RFA. In the meta-analysis of NRSI, MD in VAS was -4.12 (-4.63 to -3.61; k = 23) for knee RFA, -3.84 (-4.77 to -2.92; k = 7) for knee TAE, -4.34 (-4.96 to -3.71; k = 2) for hip RFA, -3.83 (-4.52 to -3.15; k = 3) for shoulder RFA and -4.93 (-5.58 to -4.28; k = 14) for sacroiliac joints RFA. Significant decrease in pain intensity was found also at 3, 6 and 12 months. Additionally, functional status improved at all the assessed timepoints.

CONCLUSION

minimally invasive interventional procedures can improve pain and functional status of patients affected by OA or chronic sacroiliac pain of degenerative origin. Further research is warranted in the field of inflammatory rheumatic diseases.

Clinical and radiological outcome of stand-alone percutaneous pedicle screw fixation (SAPF) versus minimally invasive transforaminal lumbar interbody fusion (MI-TLIF). A propensity-matched cohort study

In adult patients affected by degenerative disc disease with lumbar instability and chronic low back pain, spine surgery with lumbar fixation aims to reduce segmental instability and pain. Different techniques have been developed, but the optimal surgical technique remains controversial. No studies have compared the clinical and radiological outcomes between stand-alone pedicle screw fixation (SAPF) and minimally invasive transforaminal lumbar interbody fusion (MI-TLIF). This was a retrospective study. All patients who underwent surgery for single-level L4-L5 or L5-S1 lumbar stenosis, associated with minor lumbar instability and treated with SAPF or MI-TLIF techniques were included in the study. Data were collected preoperatively and at 24 monts follow-up. Clinical primary outcomes were Oswestry Disability Index (ODI) and Numerical Rating Scale (NRS). Secondary outcomes were patient satisfaction, walking ability and self reported back and leg pain. In addition, perioperative data and complications were recorded. Segmental lordosis (L4-L5 and L5-S1) and overall lumbar lordosis (L1-S1) were measured on lumbar X-Rays preoperatively and at least 24 months postoperatively. 277 patients were firstly identified. Baseline data and a minimum of two-year follow-up were available for 62 patients. After the propensity score matching, 44 patients (22 patients in the SAPF group and 22 patients in the MI-TLIF group) were matched. At 24 months follow-up, no difference between the two groups of patients in NRS (p = 0.11) and ODI scores (p = 0.21) were observed. Patients' satisfaction at follow-up was also not significantly different between the two groups. In both groups, a significant improvement in the walked distance was observed after surgery (p = 0.05) while no difference was observed regarding the type of surgery performed (p = 1.00). No differences were found in the pre- and post-operative median lumbar lordosis (p = 0.91 and p = 0.67) and the same findings were observed for lumbar segmental lordosis (p = 0.65 and p = 0.41 respectively). Significant improvements in ODI and NRS-scores were recorded after 24 months follow-up with both SAPF and MI-TLIF. No significant differences in postoperative PROMs and patients' satisfaction were observed between the groups. The results of our study indicate no superiority of either surgical technique concerning pain and functional outcomes after 24 months.

Delphi-Based Expert Consensus Statements for the Management of Percutaneous Radiofrequency Neurotomy in the Treatment of Lumbar Facet Joint Syndrome

INTRODUCTION

A modified Delphi strategy was implemented for obtaining recommendations that could be useful in the management of percutaneous radiofrequency treatment of lumbar facet joint syndrome, as the literature on the argument was poor in quality.

METHODS

An Italian research team conducted a comprehensive literature search, defined the investigation topics (diagnosis, treatment, and outcome evaluation), and developed an explorative semi-structured questionnaire. They also selected the members of the panel. After an online meeting with the participants, the board developed a structured questionnaire of 15 closed statements (round 1). A five-point Likert scale was used and the cut-off for consensus was established at a minimum of 70% of the number of respondents (level of agreement ≥ 4, agree or strongly agree). The statements without consensus were rephrased (round 2).

RESULTS

Forty-one clinicians were included in the panel and responded in both rounds. After the first round, consensus (≥ 70%) was obtained in 9 out of 15 statements. In the second round, only one out of six statements reached the threshold. The lack of consensus was observed for statements concerning the use of imaging for a diagnosis [54%, median 4, interquartile range (IQR) 3-5], number of diagnostic blocks (37%, median 4, IQR 2-4), bilateral denervation (59%, median 4, IQR 2-4), technique and number of lesions (66%, median 4, IQR 3-5), and strategy after denervation failure (68%, median 4, IQR 3-4).

CONCLUSION

Results of the Delphi investigations suggest that there is a need to define standardized protocols to address this clinical problem. This step is essential for designing high-quality studies and filling current gaps in scientific evidence.

Interventional Pain Procedures: A Narrative Review Focusing on Safety and Complications. Part 1 Injections for Spinal Pain

In recent years, there has been a considerable increase in the number of image-guided interventional procedures performed for the management of acute and chronic pain. Concomitantly, there has also been an increase in the complication rate related to these procedures. The aim of this narrative review is to summarize the primary complications associated with commonly performed image-guided (fluoroscopic- or ultrasound-guided) interventional procedures. We conclude that although complications from interventional pain procedures can be mitigated to a certain degree, they cannot be eliminated altogether. In order to avoid adverse events, patient safety should be given considerable attention and physicians should be constantly aware of the possibility of developing complications.

Real-world data and evidence in pain research: a qualitative systematic review of methods in current practice

The use of routinely collected health data (real-world data, RWD) to generate real-world evidence (RWE) for research purposes is a growing field. Computerized search methods, large electronic databases, and the development of novel statistical methods allow for valid analysis of data outside its primary clinical purpose. Here, we systematically reviewed the methodology used for RWE studies in pain research. We searched 3 databases (PubMed, EMBASE, and Web of Science) for studies using retrospective data sources comparing multiple groups or treatments. The protocol was registered under the DOI:10.17605/OSF.IO/KGVRM. A total of 65 studies were included. Of those, only 4 compared pharmacological interventions, whereas 49 investigated differences in surgical procedures, with the remaining studying alternative or psychological interventions or epidemiological factors. Most 39 studies reported significant results in their primary comparison, and an additional 12 reported comparable effectiveness. Fifty-eight studies used propensity scores to account for group differences, 38 of them using 1:1 case:control matching. Only 17 of 65 studies provided sensitivity analyses to show robustness of their findings, and only 4 studies provided links to publicly accessible protocols. RWE is a relevant construct that can provide evidence complementary to randomized controlled trials (RCTs), especially in scenarios where RCTs are difficult to conduct. The high proportion of studies reporting significant differences between groups or comparable effectiveness could imply a relevant degree of publication bias. RWD provides a potentially important resource to expand high-quality evidence beyond clinical trials, but rigorous quality standards need to be set to maximize the validity of RWE studies.

Radiofrequency Ablation for Chronic Lumbar Zygapophyseal Joint Pain Using a V-Shaped Active Tip Needle: An Observational Retrospective Study

Background

Lumbar zygapophyseal joint dysfunction represents one of the major sources of chronic low back pain. Radiofrequency ablation (RFA) using a V-shaped active tip needle may offer a larger lesion of the medial branch nerves, improving clinical outcome. The aim of our study is to evaluate the efficacy and the feasibility of RFA using V-shaped active tip needles.

Methods

This is a single-center observational retrospective study. Clinical records were screened and analyzed if they met the following inclusion criteria: adult patients (>18 years), diagnosis of chronic lumbar zygapophyseal joint pain, failure of conservative treatments, ability to provide informed consent for data analysis and publication. Exclusion criteria: lumbar pain not related to zygapophyseal joints, previous spinal/lumbar surgery, incomplete data, absence or withdrawal of informed consent. The primary outcome of the study was a change in pain intensity at follow-up. The secondary outcomes were the evaluation of quality-of-life improvement, the occurrence of adverse events and the impact on post-procedural analgesic consumption. For these purposes, pre- and post-treatment numeric rating scale (NRS), neuropathic pain 4 questions (DN4), EuroQoL - EQ-5D-3L, EQ-VAS, EQ-index and North American Spine Society (NASS) index were retrieved and analysed.

Results

Sixty-four patients were included. 7.8% of patients at 1-month (CI95% 0.026, 0.173), 37.5% at 3-month (CI95% 0.257, 0.505), 40.6% at 6-month (CI95% 0.285, 0.536) and 35.9% at 9-month (CI95% 0.243, 0.489) follow-up reported a reduction of more than 80% in NRS Statistical analysis indicated a significant change in NRS, DN4, EQ-index and EQ-5D-VAS (p-value <0.001) at the different time-points.

Conclusion

RFA using a V-shaped active tip needle might be a feasible and effective treatment for chronic lumbar zygapophyseal joint pain.

Intra-Articular Application of Sluijter-Teixera Poisson Pulsed Radiofrequency in Symptomatic Patients with Knee Osteoarthritis: Focus upon Clinical Efficacy and Safety

Purpose

To retrospectively evaluate the effectiveness of intra-articular application of Sluijter-Teixera Poisson pulsed radiofrequency (STP PRF) in knee osteoarthritis symptomatic patients with chronic pain refractory to conservative therapies.

Materials and Methods

Institutional database research of two centers identified 39 cases of knee osteoarthritis patients treated with intra-articular STP PRF. Pain prior and one-week and one-, three-, six-, and twelve-month post-STP PRF was compared by means of a numeric visual scale (NVS) questionnaire. Cardiovascular and Interventional Radiological Society of Europe (CIRSE) classification system was used for complications reporting. Mean patient age was 71.59 ± 11.99 years, mean body mass index was 30.23 ± 4.69, and male/female ratio was 9/30.

Results

Mean baseline pain score was 8.31 ± 1.70 NVS units. This was reduced to a mean value of 0.90 ± 1.50 NVS units one-week post-RF, 1.08 ± 1.53 at one month, 1.54 ± 1.88 at three months, 2.33 ± 2.17 at six months, and 3.23 ± 2.23 at 12 months of follow-up (p < 0.01). Pain decrease of more than 4 NVS units was noticed in 35/39 knees (89.7%) at first week, 36/39 knees (92.3%) at first month, 35/39 knees (89.7%) at three months, 32/39 knees (82.1%) at six months, and 25/39 knees (64.1%) at one year. There was no recurrence during the follow-up. No complication was observed.

Conclusions

Percutaneous, intra-articular application of STP PRF is an effective and safe technique for chronic pain reduction in patients with knee osteoarthritis. Results seem to be reproducible and long lasting with significant patient satisfaction at 12-month follow-up.

Intraarticular STP Radiofrequency for Painful Osteoarthritis in the Knee: A Retrospective Single Center Analysis

OBJECTIVE

Osteoarthritis (OA) is the most common cause of chronic knee pain, often a debilitating condition that can cause a significant reduction in functional capacity. Radiofrequency is a form of neuromodulation that modulates pain signal transmission and has become progressively more common as a treatment for knee pain. This retrospective study aims to evaluate the efficacy of intraarticular radiofrequency in patients with chronic knee OA pain.

MATERIALS AND METHODS

In this retrospective study, we included 129 patients undergoing intraarticular pulsed radiofrequency using the Poisson curve for energy distribution (Sluijter-Teixeira Poisson radiofrequency) (STP) from March 2018 to November 2019. Knee osteoarthritis severity was assessed prior to the procedure using the Lequesne Index, classifying patients into six groups based on level of severity. Pain intensity was assessed through a 10-cm visual analog scale (VAS), and level of patient satisfaction was assessed through a questionnaire.

RESULTS

In the sample, pain reduction as measured by VAS compared to baseline prior to the procedure was statistically significant immediately following the procedure, at 30 days and at 90 days (p<0.001); this difference was less significant at 180 days (p<0.005). Efficacy in patients with moderate to severe disability was considerably greater than in patients with very severe to extremely severe disability. 57.36% reported that they were very satisfied, 29.46% satisfied, 9.3% neither satisfied nor dissatisfied, 2.33% dissatisfied, and 1.55% very dissatisfied.

CONCLUSION

Our results suggest that STP radiofrequency may be a safe and effective procedure for knee OA, able to significantly reduce VAS scores at 1 month and 3 months compared to baseline. Based on our results, a key factor to consider when treating knee OA with STP radiofrequency is that it is more effective among patients with a lower level of disability. Due to the retrospective observational study design, prospective longitudinal investigation is required to further support the recommendation of STP radiofrequency for knee OA.

Practical Advices for Treating Chronic Pain in the Time of COVID-19: A Narrative Review Focusing on Interventional Techniques

BACKGROUND

Since the management of chronic pain has become even more challenging secondary to the occurrence of SARS-CoV-2 outbreaks, we developed an exhaustive narrative review of the scientific literature, providing practical advices regarding the management of chronic pain in patients with suspected, presumed, or confirmed SARS-CoV-2 infection. We focused particularly on interventional procedures, where physicians are in closer contact with patients.

METHODS

Narrative Review of the most relevant articles published between June and December of 2020 that focused on the treatment of chronic pain in COVID-19 patients.

RESULTS

Careful triage of patients is mandatory in order to avoid overcrowding of hospital spaces. Telemedicine could represent a promising tool to replace in-person visits and as a screening tool prior to admitting patients to hospitals. Opioid medications can affect the immune response, and therefore, care should be taken prior to initiating new treatments and increasing dosages. Epidural steroids should be avoided or limited to the lowest effective dose. Non urgent interventional procedures such as spinal cord stimulation and intrathecal pumps should be postponed. The use of personal protective equipment and disinfectants represent an important component of the strategy to prevent viral spread to operators and cross-infection between patients due to the SARS-CoV-2 outbreaks.