What is the evidence for Genicular Nerve Blocks in patients with knee osteoarthritis for pain reduction?
AMSTAR Rating
Summary
Patient Population:
231 participants (Male = 56, Female = 175) with a mean age of 64.21 were evaluated in this meta-analysis of five randomized controlled trials (RCTs). Four studies included patients with grade 2 to 4 knee osteoarthritis (OA), and one study included patients with grade 3 to 4 knee OA.
Intervention:
All studies used genicular nerve blocks (GNB) consisting of 6mL of lidocaine or 6mL of lidocaine plus 20mg of triamcinolone (TA) injected at three separate target sites: the superior lateral, superior medial, and inferior medial genicular nerves. All studies used ultrasound (US) to guide GNB in their intervention groups (n=115).
Comparison:
This meta-analysis only included RCTs that compared GNB to placebo or intra-articular (IA) therapies (n=116).
Outcome:
A random-effects model and the generic inverse variance method were used in this meta-analysis. Outcome measures evaluating pain included the Visual Analog Scale (VAS) and the Numeric Rating Scale (NSR). The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and the Oxford Knee Score (OKS) were used to assess functional outcomes.
- Intervention groups receiving GNB demonstrated a statistically significant reduction of pain at 1 month (SMD = 1.68 [95% CI, 1.08, 2.29]; P = 0.00001; I2 = 72%) and 3 months (SMD = 1.18 [95% CI, 2.09, 2.09]; P = 0.01; I2 = 89%) compared to control groups.
- These results are found to exceed the minimally clinically important difference (MCID) for pain defined as standard mean difference (SMD) = 0.39 [95% CI, 0.20, 0.50] at both 1 and 3 months, established for non-surgical strategies for knee OA.
- Intervention groups also showed statistically significant improvement in function at 1 month (SMD = 1.00 [95% CI, 0.30, 1.70]; P = 0.0005; I2 = 83%) and 3 months (SMD = 0.49 [95% CI, 0.23, 0.76]; P = 0.0002; I2 = 0%) compared to control groups.
Guideline Recommendations
| Source | Recommendation |
|---|---|
| NO GUIDELINES (2025) | N/A |
Outcomes Assessed
- Benefit
- Harm
- Inconclusive
Pain
1 month
3 months
Function
1 month
3 months
US v. Fluoroscopy
Pain and Function
Relevant Clinical Info
Ragab, A.R., Hegab, S., Elnemr, R. et al. Intra-articular corticosteroid injection and genicular nerve block under ultrasound guidance in pain control of knee osteoarthritis. Egypt J Radiol Nucl Med 52, 196 (2021). https://doi.org/10.1186/s43055-021-00577-z
Ragab et al. (2021) was the most recent RCT included in this meta-analysis and was assessed to have low overall bias risk according to Cochrane guidelines. This randomized, prospective, blinded study aimed to evaluate the efficacy of US-guided intra-articular corticosteroid injection (IACSI) and GNB to control knee OA. The GNB group (n=20, Male=5, Female=15) were injected with a mixture of 20 mg of Triamcinolone Acetonide (TA) and 6 mL of lidocaine, equally divided and targeted at genicular nerve branches via injection near each of the three genicular arteries. The IACSI group (n=20, Male=4, Female=16) was injected with a mixture of 1mL TA (40mg) and 5mL lidocaine inside the suprapatellar bursa. While both groups showed decreased pain and improved functional scores, the mean VAS decreased by 13.6, 14.1, and 3.65 points more in the GNB group compared to IACSI group at 2, 4, and 8 weeks, respectively (p < 0.001 for groups at 2 and 4 weeks, and p<0.006 at 8 weeks). Similarly, the mean OKS decreased by 7.05, 8.5, and 3.25 points more in the GNB group compared to IACSI group at 2, 4, and 8 weeks, respectively (p < 0.001 for both groups at 2, 4, and 8 weeks).
Participant Information
of participants
were Female
The sample size was 231
Mean age of 64.21 years.
There were 5 studies used.
