Ultrasound-guided pulsed radiofrequency of the saphenous nerve for knee osteoarthritis pain: a pilot randomized trial

Efficacy and safety of minimally invasive interventions targeting the genicular nerves for knee osteoarthritis: A meta-analysis

IMPORTANCE

Osteoarthritis (OA) is a prevalent and disabling joint disorder. Minimally invasive interventions targeting the genicular nerves are widely used for the clinical management of knee OA, but evidence on their efficacy and safety remains uncertain.

OBJECTIVE

To assess the efficacy and safety of minimally invasive interventions targeting the genicular nerves in knee OA.

DATA SOURCES

We searched MEDLINE, Embase, CENTRAL and clinical trial registries, from inception to August 2024.

STUDY SELECTION

We included randomised controlled trials evaluating minimally invasive interventions targeting the genicular nerves in patients with knee OA. Comparators included sham/placebo (main comparison), intra-articular injections, and usual care.

DATA EXTRACTION AND SYNTHESIS

Data were extracted independently by two reviewers following the PRISMA guidelines. Risk of bias was assessed using the Cochrane RoB-2 tool, and evidence certainty was evaluated according to the GRADE approach. A random-effects meta-analysis was conducted.

MAIN OUTCOME(S) AND MEASURES(S)

The primary outcomes were pain intensity, physical function, and serious adverse events. Secondary outcomes included quality of life and patient-reported global perceived effect.

RESULTS

Twenty-five trials were included (n= 2049) evaluating radiofrequency ablation (RFA), genicular nerve block (GNB) and cryoneurolysis. The certainty of evidence was consistently low to very low across all comparisons. RFA may provide moderate short-term pain relief (0 - 10 scale) compared to sham at 4 weeks (MD -1.70, 95% CI -3.03 to -0.36) and 12 weeks (MD -1.86, 95% CI -2.82 to -0.89), but there was no benefit at 24 and 48 weeks, and no improvements in function at any time point. The evidence is very uncertain for GNB, with only a single trial suggesting small pain reduction and moderate functional improvements at 4 weeks. For cryoneurolysis, very low certainty evidence suggests minimal short-term effects on pain and function. No differences in serious adverse events were observed between minimally invasive interventions and sham/placebo.

CONCLUSIONS AND RELEVANCE

The evidence supporting the use of RFA for the management of knee OA is highly uncertain, with modest, short-term benefits that are not sustained. Given the very low certainty of current data, we advise against its routine use until more robust evidence is available.

PROTOCOL REGISTRATION

PROSPERO - CRD42023454756.

Surfer's neurapraxia - an uncommon surfing injury of the saphenous nerve

Surfer's neurapraxia is a rare surfing injury of the saphenous nerve secondary to persistent compression of the saphenous nerve along the medial thigh by the surfboard when paddling prone and while sitting upright on the board waiting for a wave. Symptoms may be nonspecific and consist of pain in the medial thigh with or without radiation along the saphenous nerve distribution (medial leg, medial ankle, medial arch of the foot). The saphenous nerve tension test can be utilized to reproduce the symptoms of surfer's neurapraxia. Treatment consists of conservative management while refractory cases may benefit from injection with local anesthetic. The authors propose the Obana Plan (WATER) for prevention of surfer's neurapraxia, consisting of Wetsuits, Abduction, Timing, Exercise, and Rest. Overall, surfer's neurapraxia is a benign condition that can be prevented and managed conservatively.

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.

Infrapatellar Branch of the Saphenous Nerve: Therapeutic Approaches to Chronic Knee Pain

PURPOSE OF REVIEW

The infrapatellar branch of the saphenous nerve (IPS) is an under-investigated nerve that can be a source of chronic knee pain. This literature review aims to deliver an up-to-date review of chronic pain transmitted via the IPS along with therapeutic approaches available for pain refractory to conservative measures.

RECENT FINDINGS

Knee pain transmitted via the IPS can arise from several etiologies. Damage to the IPS is often iatrogenic and develops following total knee arthroplasty, anterior cruciate ligament reconstruction, and other knee surgical procedures. Other causes of IPS-derived pain include entrapment of the nerve, neuromas, Schwannomas, and pain from knee osteoarthritis transmitted through the IPS.This article investigated therapeutic approaches to pain derived from the IPS. Common approaches included radiofrequency ablation, neuroma excisions, Schwannoma excision, nerve blocks, surgical exploration, surgical release of an entrapped nerve, cryoablation, and peripheral nerve stimulation. Pain scores, duration of pain relief, adverse events, and secondary outcomes were all included in this review. A subset of the patient population experiences chronic pain deriving from the IPS that is refractory to conservative treatment measures. This review aims to evaluate the etiologies and therapeutic approaches for chronic pain arising from the IPS refractory to conservative treatments.

Editorial Commentary: Radiofrequency Ablation for Patients With Osteoarthritis of the Knee Could Be Indicated for Patients Failing Conventional Nonoperative Treatment and Wishing to Avoid Total Knee Arthroplasty

Patients with knee osteoarthritis are constantly looking for ways to combat their pain and improve their quality of life. As newer treatments present themselves, it is up to the orthopaedic specialists to provide the best treatment possible. Radiofrequency ablation, usually administered by a pain management specialist, has shown to be an acceptable alternative treatment and should be considered in the management of osteoarthritis. It should be considered for patients who have failed nonoperative treatments and are not interested in pursuing total knee arthroplasty, and possibly for patients who have persistent pain after total knee arthroplasty.

Radiofrequency Ablation in Cooled Monopolar or Conventional Bipolar Modality Yields More Beneficial Short-Term Clinical Outcomes Versus Other Treatments for Knee Osteoarthritis: A Systematic Review and Network Meta-Analysis of Randomized Controlled Trials

PURPOSE

To evaluate various radiofrequency ablation (RFA) treatments for knee osteoarthritis (OA) and determine the best modality, target, number of electrodes, and image guidance for improving knee pain and function.

METHODS

Electronic databases were searched for randomized controlled trials (RCTs) comparing the efficacy of RFA treatments for knee OA from inception up to September 30, 2021. The primary outcome was the visual analog scale (VAS), and the secondary outcome was the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). Bayesian network meta-analysis was performed to synthesize the mean difference (MD) and rank the comparative effectiveness of treatments.

RESULTS

A total of 21 eligible RCTs (from 2011 to 2021, involving 1,818 patients) with 8 RFA treatments, 6 intra-articular injections, NSAIDS, exercise, and placebo were assessed. Conventional bipolar genicular nerve RFA (GNRFA) had the greatest net benefit on the VAS at 6 months (MD, -5.5; 95% confidence interval [CI], -4.3 to -6.7; SUCRA, .98). And cooled monopolar GNRFA had the greatest net benefit on the WOMAC at 6 months (MD, -33; 95% CI, -37 to -29; SUCRA, .99). In conventional and pulsed modalities, bipolar RFA was associated with a significant decrease in VAS and WOMAC than monopolar RFA. Combining pulsed intra-articular RFA and platelet-rich plasma injection had no additional positive effects on VAS or WOMAC at 3 months.

CONCLUSIONS

RFA is effective in improving both knee pain and function in patients with OA, at least in the short term (6 months). Patients respond better to the cooled modality than the conventional and pulsed modalities. Bipolar is more effective than monopolar for improving pain and function in conventional and pulsed modalities. Fluoroscopy and ultrasound guidance showed no differences in improving pain and function. The effectiveness of RFA in cooled modality using bipolar or in combination with various intra-articular injections remains to be compared.

LEVEL OF EVIDENCE

II, systematic review and meta-analysis of Level I and II studies.

Efficacy and safety of radiofrequency treatment for improving knee pain and function in knee osteoarthritis: a meta-analysis of randomized controlled trials

Background

The clinical utility of radiofrequency (RF) in patients with knee osteoarthritis (OA) remains unclear. We conducted a meta-analysis to systematically evaluate the efficacy and safety of RF treatment in patients with knee OA.

Methods

Searches of the PubMed, Web of Science, EMBASE, Cochrane Library, China National Knowledge Infrastructure, and Wanfang Data databases were performed through August 30, 2021. The major outcomes from published randomized controlled trials (RCTs) involving patients with knee OA were compared between RF and control groups, including Visual Analogue Scale (VAS) or Numerical Rating Scale (NRS) scores, the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), Oxford Knee Score (OKS), Global Perceived Effect (GPE) scale, and adverse effects at available follow-up times.

Results

Fifteen RCTs involving 1009 patients were included in this meta-analysis, and the results demonstrated that RF treatment correlated with improvements in pain relief (VAS/NRS score, all P < 0.001) and knee function (WOMAC, all P < 0.001) at 1–2, 4, 12, and 24 weeks after treatment as well as patients’ degree of satisfaction with treatment effectiveness (GPE scale, 12 weeks, P < 0.001). OKSs did not differ significantly between the two groups. Moreover, treatment with RF did not significantly increase adverse effects. Subgroup analysis of knee pain indicated that the efficacy of RF treatment targeting the genicular nerve was significantly better than intra-articular RF at 12 weeks after treatment (P = 0.03).

Conclusions

This meta-analysis showed that RF is an efficacious and safe treatment for relieving knee pain and improving knee function in patients with knee OA.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13018-021-02906-4.