Functional Outcomes and Physical Performance of Knee Osteoarthritis Patients After Ultrasound-Guided Genicular Nerve Radiofrequency Ablation

Chemical neurolysis of genicular nerves for chronic non-cancer knee pain: a scoping review

OBJECTIVE

Chemical neurolysis of the genicular nerves is a treatment option for intractable non-cancer knee pain. This scoping review synthesizes the available literature on the effectiveness, adverse events, and procedural techniques of chemical neurolysis of genicular nerves for the management of knee pain.

DESIGN

Scoping review.

SETTING

All clinical and research settings.

SUBJECTS

Adult participants with chronic non-cancer knee pain undergoing chemical neurolysis of genicular nerves.

METHODS

A literature search in MEDLINE, EMBASE, and Cochrane Library was conducted up to September 4, 2023. Articles were searched via terms and keywords relating to "knee," "pain," "knee osteoarthritis," "ablation," "alcohol," "phenol," and "chemical neurolysis." Included articles were full-text primary studies and in English. Data were extracted by 2 independent reviewers using an electronic database.

RESULTS

Eight studies were included in this review (including 1 randomized controlled trial), comprising 192 patients. Of the 8 studies, 4 used phenol, 3 used alcohol, and 1 used either alcohol or phenol for chemical neurolysis. Fluoroscopy, ultrasound guidance, or both were used for nerve target identification. All studies demonstrated that chemical neurolysis resulted in improved pain or functional outcomes, with no serious adverse events reported.

CONCLUSIONS

Chemical neurolysis of the genicular nerves is a promising treatment strategy for chronic knee pain. Interpretation of the available studies is limited by study heterogeneity and small sample sizes. High-quality randomized controlled trials are required to clarify the selection of appropriate nerve targets and choice of image guidance and to compare with other ablative modalities.

STUDY REGISTRATION

Open Science Framework (https://osf.io/jg8wh).

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.

Genicular nerve radiofrequency ablation practice patterns: A survey study of the International Pain and Spine Interventional Society

Introduction

Chronic knee pain often results from degenerative conditions such as knee osteoarthritis (OA) and can worsen after surgical interventions like total knee arthroplasty (TKA). Knee OA affects approximately 86 million individuals globally, leading to decreased function, mobility limitations, and disability. While TKA is a common surgical treatment for refractory knee OA, though up to 20 % of patients experience chronic post-operative knee pain worse than their pre-operative pain. Genicular nerve radiofrequency ablation (GnRFA) has emerged as a promising intervention for knee OA pain unresponsive to conservative management and for chronic post-TKA pain. GnRFA is an evidence-based technique supported by multiple prospective cohort studies and randomized controlled trials (RCTs). However, practice patterns and GnRFA techniques vary, and no peer-reviewed publication has yet quantified these variations in real-world clinical practice.

Objective

This study aims to understand the practice patterns of interventional pain physicians regarding patient selection, use of prognostic blocks, imaging, nerve targets, GnRFA types, and GnRFA techniques in treating knee pain secondary to OA or persistent post-TKA pain.

Methods

An anonymous 29-question survey was distributed via electronic mail to members of the International Pain and Spine Intervention Society (IPSIS) from January 16, 2024, to February 29, 2024. The survey assessed practice patterns related to patient selection, prognostic block use, and GnRFA techniques. Data were collected and stored using REDCap software, with descriptive statistics calculated.

Results

A total of 150 completed surveys were analyzed, representing a completion rate of 2.0 % of surveys sent, 3.5 % of emails opened, and 56.8 % of those who clicked on the survey link. Respondents generally use common selection protocols regarding OA grade (Kelgren-Lawrence 3 and 4), duration of failed conservative care (3-6 months), a single anesthetic block paradigm, and use of fluoroscopic guidance for the GnRFA procedure. More variability was reported between respondents regarding the volume of anesthetic used during prognostic blocks, the threshold to consider a prognostic block "positive," the technology used, and nerves targeted during the GnRFA procedure.

Conclusion

The study provides valuable insights into the current practice patterns of GnRFA among interventional pain physicians. While there is consensus on some aspects of patient selection and procedural techniques, significant variability exists in prognostic block protocols and nerve targets for GnRFA. These findings highlight the need for further research to explore the long-term efficacy and safety of GnRFA and to standardize techniques and protocols across different practice settings, ultimately improving patient outcomes and quality of life. The low response rate may limit generalizability, and the survey did not include data on active tip sizes used for ablation or whether other procedures should be exhausted before resorting to GnRFA. Additionally, a survey to IPSIS membership only may not fully represent a diverse cohort of pain management specialists, potentially introducing sampling bias. Future studies should include members from a broader range of professional organizations to enhance representativeness.