Cooled radiofrequency ablation versus cryoneurolysis of the genicular nerves for the symptomatic pain management in knee osteoarthritis: a study protocol of a prospective, randomized, single-blinded clinical trial

Advances in Interventional Radiology Technology for the Treatment of Knee Osteoarthritis

Minimally invasive interventional radiology procedures play an adjunctive role in treating the symptoms of osteoarthritis (OA) with the hopes of delaying total knee arthroplasty (TKA). However, currently available intra-articular injections offer only short-term benefits. This has led to evolution of new techniques such as genicular artery embolization and genicular nerve ablation, which show benefit in pain control and quality of life, especially for mild-to-moderate OA, positioning these techniques as potential alternatives to intra-articular injections to help delay TKA.

Sacroiliac joint pain: what treatment and when

INTRODUCTION

Spinal and non-spinal pathologies can cause low back pain. Non-spinal sources of low back pain include the sacroiliac joint (SIJ) and the hip. SIJ pain can be treated either conservatively or surgically. Current strategies for managing sacroiliac joint pain are debated, and limited evidence exists.

AREAS COVERED

The present expert opinion updates current evidence on conservative and surgical modalities for SIJ pain.

EXPERT OPINION

Surgical management for SIJ pain is effective. However, it exposes patients to surgery and, therefore, related complications. Conservative management may be implemented in patients with moderate SIJ pain, with less than six months of symptoms, or not eligible for surgery. Several noninvasive modalities are available, mostly centered on intra-articular injections. Corticosteroids, platelet-rich plasma, and stem cells have only midterm lasting effects, at most for nine months. Radiofrequency ablation is another methodology for pain relief. Both continuous and pulsatile radiofrequency ablation are associated with good outcomes. SIJ fusion can be performed using different techniques; however, a clear recommendation on the most appropriate modality for the management of SIJ pain is still debated.

Applications of Cryoneurolysis in Chronic Pain Management: a Review of the Current Literature

PURPOSE OF REVIEW

The purpose of this review is to evaluate and summarize the literature investigating cryoneurolysis in the treatment of various chronic pain pathologies.

RECENT FINDINGS

There is an increasing amount of interest in the use of cryoneurolysis in chronic pain, and various studies have investigated its use in lumbar facet joint pain, SI joint pain, post-thoracotomy syndrome, temporomandibular joint pain, chronic knee pain, phantom limb pain, neuropathic pain, and abdominal pain. Numerous retrospective studies and a more limited number of prospective, sham-controlled prospective studies suggest the efficacy of cryoneurolysis in managing these chronic pain pathologies with a low complication rate. However, more blinded, controlled, prospective studies comparing cryoneurolysis to other techniques are needed to clarify its relative risks and advantages.

Efficacy and Safety of Cryoablation Compared with Cooled Radiofrequency Ablation of Genicular Nerves in Advanced Osteoarthritis of the Knee: A Study Protocol of Single-Centric, Assessor-Blinded, Randomized, Parallel-Group, Non-inferiority Study

PURPOSE

In patients with symptomatic osteoarthritis knee (OAK), cryoneurolysis (CRYO) and cooled radiofrequency ablation (C-RFA) are reported to be effective and safe; however, they have not been compared directly. The objective of this study is to compare CRYO and C-RFA of the genicular nerve (GN) in terms of efficacy and safety profile in patients with Kellgren and Lawrence (KL) grade ≥ 3 OAK.

METHODS

This single-centric, assessor-blinded, randomized, parallel-group, non-inferiority study will include 80 patients with KL grade ≥ 3 OAK. The patients with ≥ 50% pain relief on diagnostic block of three GNs will be randomized to one of the two groups, i.e., CRYO (n = 40) or C-RFA (n = 40). The three target GNs for the interventions will include: superior medial, superior lateral, and inferior medial. The primary outcome will be efficacy of CRYO or C-RFA at 2, 12, and 24 weeks post-procedure based on the 11-point Numerical Pain Rating Scale. The secondary outcomes will be functional improvement based on 12-item Oxford Knee Score and safety of both the procedures. The study is registered in the Clinical Trials Registry-India.

CONCLUSION

CRYO and C-RFA provide pain relief and improve functional outcome by preventing transmission of pain signals, though by distinct mechanisms. While C-RFA is an established treatment modality, recent evidence supports CRYO in patients with OAK. This study intends to demonstrate non-inferiority of CRYO against C-RFA, thereby supporting the use of CRYO as an additional treatment modality in patients with KL grade ≥ 3 OAK.

Temperature-Mediated Neural Interventions in Knee Osteoarthritis: a Review of Cryoneurolysis and Cooled Radiofrequency Ablation with Ultrasound Guidance

PURPOSE OF REVIEW

Knee osteoarthritis is a debilitating chronic disease affecting nearly half of the world's population at some point in their lives. Treatment of pain and loss of function associated with this disease has been limited. In this review, we seek to explore how neural interventions with ultrasound guidance may be an emerging option for non-pharmacologic pain relief in patients with knee osteoarthritis.

RECENT FINDINGS

Cryoneurolysis techniques have been demonstrated to provide pain relief out to 150 days post-treatment in knee osteoarthritis in select individuals. There have also been studies of cryoneurolysis pre-operatively to total knee replacement providing reduced pain, reduced opioid use post-operatively, and shorter hospital length of stay. Cooled radiofrequency ablation (CRFA) has been demonstrated to significantly reduce pain, improve functionality, and reduce pharmacologic needs in knee osteoarthritis out to 2 years. Both interventions appear to have increased accuracy with ultrasound, and CRFA appears to be associated with improved patient outcomes. The research demonstrates the efficacy of both cryoneurolysis and cooled radiofrequency ablation in the treatment of knee osteoarthritis. Ultrasound guidance in neurolysis provides an additional tool with real-time, high-accuracy nerve localization. These therapies should be considered for certain patients to assist in pain management in the non-operative and post-operative phase of knee osteoarthritis management. Further research is needed to further define the long-term effects and the long-term utility of the techniques in knee pain.