Ultrasound-guided genicular nerves block vs. local infiltration analgesia for total knee arthroplasty: a randomised controlled non-inferiority trial

Motor-sparing regional anaesthesia for total knee arthroplasty: a narrative and systematic literature review

Total knee arthroplasty is a life-changing surgical procedure that is associated with a high incidence of severe postoperative pain. Key to enhancing recovery after surgery is effective analgesia and early mobilisation. Innovations in motor-sparing regional anaesthesia techniques that have improved recovery include targeted surgical local infiltration analgesia, adductor canal blockade, genicular nerve blocks, and the infiltration between the popliteal artery and posterior capsule of the knee (iPACK) block. This narrative review discusses the current available motor-sparing regional anaesthetic techniques and assesses the evidence supporting each.

Effects of Genicular Nerve Blocks in Combination With an Adductor Canal Block in Patients Undergoing Arthroscopic Knee Surgery: A Randomized Controlled Trial

BACKGROUND AND OBJECTIVES

Arthroscopic knee surgery is increasingly popular. Optimal postoperative pain management enhances patient satisfaction and minimizes hospitalization. Numerous studies have demonstrated the benefits of adductor canal blocks (ACBs) and genicular nerve blocks (GNBs) in postoperative analgesia. This study aims to evaluate the efficacy of adding GNBs to an ACB in reducing postoperative pain scores compared to an ACB alone. Additionally, it seeks to compare secondary outcomes, including opioid consumption, motor blockade, nausea and vomiting, rash, and itching during the postoperative period.

METHOD

This prospective, randomized, controlled clinical trial included 49 patients undergoing arthroscopic knee surgery. The study group received a GNB with 0.25% bupivacaine (3 mL) at each quadrant of the knee, except for the inferolateral quadrant, in combination with an ACB using 0.25% bupivacaine (20 mL). The control group received an ACB alone. Fentanyl (1-2 mcg/kg IV) was administered as rescue analgesia during the perioperative period. Pain scores (visual analog score (VAS)), cumulative opioid consumption, motor blockade, and incidences of postoperative nausea and vomiting (PONV) and itching were assessed at six, 12, 24, and 48 hours postoperatively.

RESULTS

No statistically significant differences in median pain scores were observed between the groups. However, postoperative opioid consumption was significantly lower in the study group, with median values (interquartile range (IQR)) of 0 (0, 30) at 12, 24, and 48 hours postoperatively compared to the control group (p ≤ 0.001). Additionally, no significant differences were found between groups regarding motor blockade or opioid-related side effects.

CONCLUSION

Adding GNBs to an ACB did not demonstrate superiority in reducing postoperative pain scores. However, it effectively reduced perioperative opioid consumption at 12 to 48 hours postoperatively without increasing adverse effects such as nausea, vomiting, or motor blockade. These findings highlight the potential of GNBs as a valuable component of postoperative pain management strategies for arthroscopic knee surgery.

Effect of Genicular Nerve Block (GNB) on Pain in Lesions of the Knee Joint: A Meta-Analysis of Randomized Controlled Trials

To explore the effect of genicular nerve block (GNB) on pain in lesions of the knee joint. Computerized searches of randomized controlled trials were conducted in PubMed, EMbase, Cochrane Library, and Web of Science, with a search time frame until January 2024. Methodological and experimental quality was assessed using the risk of bias assessment tool recommended by the Cochrane Handbook. A meta-analysis was conducted of the pain score (as the primary outcome measure) using Review Manager 5.4 and Stata 17. Thirteen studies involving a total of 731 patients were ultimately included. In the comparison of GNB and non-GNB, the analysis results of analgesic effects at all visits showed [SMD=-0.51, 95% CI (-0.89, -0.14)]. Analysis of analgesic effects at a visit at 1 month showed [SMD=-0.79, 95% CI (-1.55, -0.02)]. Subgroup analysis for the control group showed [SMD=-4.07,9 5% CI (-4.10, -1.84)]. Currently, available evidence suggests that GNB may be an effective analgesic therapy and superior to other regimens in the treatment of lesions of the knee joint.

Quantitative analysis of genicular nerve block spread and variability: Anatomical correlations and clinical implications

BACKGROUND

Despite advancements in anaesthesiology and regional anaesthesia, the three-dimensional spread of local anaesthetics is still poorly understood. This study investigates the pericapsular spread of radiopaque contrast after ultrasound-guided genicular nerve block in cadaveric knees using CT reconstruction. The aim is to assess the reproducibility, accuracy, and variability of this technique in order to improve safety and effectiveness.

METHODS

We used a four-stage methodology that involved performing genicular nerve block on cadaveric knees, acquiring data using high-resolution ultrasound and helical CT imaging, performing segmentation and surface reconstruction of the CT images, and analysing the data quantitively to determine the spread of the infiltrate in each genicular nerve region. Coefficients of variation were calculated to estimate the spread and reproducibility of each genicular nerve block.

RESULTS

Our results revealed significant variability in spread in all genicular nerve blocks, particularly around the recurrent genicular nerve. Despite this variability, the spread-particularly along the medial-lateral and anterior-posterior axes-showed moderate consistency. Furthermore, the regions covered by 80% of the spread closely matched the pericapsular distribution of the genicular nerves of the knee.

CONCLUSIONS

Notable variability in spread was observed in genicular nerve blocks, particularly around the recurrent genicular nerve. However, the spread showed moderate consistency and aligns closely with the pericapsular nerve distribution of the knee. Future studies should combine quantitative analysis with anatomical dissection to further investigate the involvement of the deep peroneal motor branch.

Nerve Blocks for Post-Surgical Pain Management: A Narrative Review of Current Research

Opioids remain the mainstay of post-surgical pain management; however, concerns regarding addiction and side effects necessitate the exploration of alternatives. This narrative review highlights the potential of nerve blocks as a safe and effective strategy for post-surgical pain control. This review explores the use of various nerve block techniques tailored to specific surgical procedures. These include nerve blocks for abdominal surgeries; fascial plane blocks for chest surgeries; nerve blocks for arm surgeries; and nerve blocks for lower limb surgery including; femoral, hip, and knee surgeries. By targeting specific nerves, these blocks can provide targeted pain relief without the negative side effects associated with opioids. Emerging evidence suggests that nerve blocks can be as effective as opioids in managing pain, while potentially offering additional benefits such as faster recovery, improved patient satisfaction, and reduced reliance on opioids. However, the effectiveness of nerve blocks varies depending on type of surgery, and in individual patients. Rebound pain, which temporary increase in pain after a block wears off, can occur. In addition, some techniques require specialized guidance for accurate placement. In conclusion, nerve blocks show great promise as effective alternatives for managing post-surgical pain. They can reduce the need for opioids and their side effects, leading to better patient outcomes and satisfaction. Future studies should assess the long-term impacts of specific nerve blocks on mortality rates, cost-effectiveness, and their incorporation into multimodal pain management approaches to further enhance post-surgical care.

Adductor canal block combined with genicular nerve block versus local infiltration analgesia for total knee arthroplasty: a randomized noninferiority trial

OBJECTIVE

This randomized controlled and double-blind study aimed to investigate whether the analgesic effect of the adductor canal block (ACB) combined with the genicular nerve block (GNB) after total knee arthroplasty is noninferior to that of the adductor canal block combined with local infiltration analgesia (LIA).

METHODS

A total of 102 patients undergoing total knee arthroplasty under general anesthesia were included and randomly divided into: ACB + GNB and ACB + LIA groups; the ACB + LIA group received 80 mL of 0.2% ropivacaine with adrenaline 10 µg/mL for LIA, whereas the ACB + GNB group received 4 mL of 0.2% ropivacaine for the blockade of five peri-knee nerves. The primary outcome was the median difference in the visual analog scale scores at rest at 24 h between the two groups. Secondary outcomes involved the median differences in the pain scores at other time points. Other outcomes included the cumulative dosage of opioids calculated in morphine equivalents in the first 24 h and indicators related to knee joint functional recovery.

RESULTS

In total, 36 and 38 patients were included in the ACB + GNB and ACB + LIA groups, respectively. We found that the median difference (95% confidence internal) in postoperative rest pain at 24 h (noninferiority criteria, △ = 1) was - 0.5 (- 1 to 0, p = 0.002). The median difference in cumulative opioid consumption was 1 mg (- 1 to 3, p = 0.019), meeting the noninferiority criteria, △ = 7.7 mg.

CONCLUSIONS

ACB combined with GNB provides noninferior analgesia compared to ACB with LIA on the first day after total knee arthroplasty while significantly reducing local anesthetic use.

TRIAL REGISTRATION

Name of the Registry: Chinese Clinical Trial Registry; Trial Registration Number: ChiCTR2300074274; Date of Registration. August 2, 2023.

Intraoperative landmark-based genicular nerve block versus periarticular infiltration for postoperative analgesia in total knee arthroplasty: a randomized non-inferiority trial

INTRODUCTION

Genicular nerve blocks (GNBs) are an emerging technique that have been used as a part of multimodal analgesia for total knee arthroplasty. The efficacy of intraoperative landmark-based GNBs, a recently introduced technique, has been established. We hypothesized that it would provide non-inferior postoperative analgesia compared with periarticular infiltration (PAI) when combined with continuous adductor canal block.

METHODS

This study randomized 140 patients undergoing total knee arthroplasty to receive either intraoperative landmark-based GNB (GNB group) or PAI (PAI group), with 139 completing the study. The primary outcomes were the pain scores at rest and during movement at 12 hours postoperatively on an 11-point Numerical Rating Scale; the non-inferiority margin was 1. Pain scores at additional time points, intravenous morphine consumption, time to first rescue analgesia, functional performance and muscle strength tests, and sleep disturbance were also assessed.

RESULTS

At 12 hours postoperatively, the PAI and GNB groups had median resting pain scores of 0 (0-2) and 0 (0-2), respectively. The median difference was 0 (95% CI -0.4 to 0.4, p=1), with the 95% CI upper limit below the prespecified non-inferiority margin. The median pain score during movement was 1.5 (0-2.3) and 2 (1-3.1) in the PAI and GNB groups, respectively. The median difference was 0.9 (95% CI 0.3 to 1.6, p=0.004), failing to demonstrate non-inferiority. The GNB group had higher intravenous morphine consumption at 12 hours postoperatively and a shorter time to first rescue analgesia.

CONCLUSIONS

GNB compared with PAI provides non-inferior resting pain relief. Non-inferiority was not established for pain during movement.

TRIAL REGISTRATION NUMBER

TCTR20220406001 (www.thaiclinicaltrials.org).

Comparison of genicular nerve block with adductor canal block for postoperative pain management in patients undergoing arthroscopic knee ligament reconstruction: A randomised controlled trial

Background and Aims

Genicular nerve block (GNB) is beneficial in early ambulation and faster patient discharge since it selectively blocks articular branches and is motor-sparing. This study aimed to compare the analgesic efficacy of ultrasound (US)-guided GNB with adductor canal block (ACB) in patients undergoing arthroscopic anterior cruciate ligament reconstruction (ACLR).

Methods

This randomised, double-blind study was conducted on 38 adults undergoing arthroscopic ACLR. Patients in Group GNB (n = 19) received US-guided GNB with 3 ml of 0.25% bupivacaine and 2 mg dexamethasone. Patients in Group ACB (n = 19) received US-guided ACB with 20 ml of 0.25% bupivacaine with 6 mg dexamethasone. Postoperative rescue analgesia was provided by intravenous Patient Controlled Analgesia (PCA) with morphine. The primary outcome was Numerical Rating Scale (NRS) pain scores over 24 h. The secondary outcome was the duration of analgesia and 24-h morphine consumption. The Chi-square test was used to test the statistical significance between categorical variables. Independent t-test or Mann-Whitney U test was used to compare continuous variables.

Results

NRS scores at rest and physical activity at 24 h were similar in both the groups (P = 0.429 and P = 0.101, respectively). The mean time to rescue analgesia was comparable in both groups (Group GNB: 820.79 [483.65] min [95% confidence interval {CI}: 603.31-1038.27] and Group ACB: 858.95 [460.06] min [95% CI: 652.08, 1065.82], P = 0.805), and the mean 24-h morphine consumption was also comparable in both groups (P = 1.000).

Conclusion

US-guided GNB has an analgesic efficacy similar to US-guided ACB for patients undergoing arthroscopic ACLR.

Ultrasound-guided quadratus lumborum block: a powerful way for reducing postoperative pain

Ultrasound-guided quadratus lumborum block (QLB) has been gradually carried out in clinical practice. However, some clinical evidence is contradictory, and no studies have summarized and described these results. The authors reviewed the anatomical characteristics of QLB and summarized the advantages and disadvantages of four puncture methods, so as to facilitate the clinical application of QLB.

Comparison of ultrasound-guided genicular nerve block and knee periarticular infiltration for postoperative pain and functional outcomes in knee arthroplasty - A randomised trial

Background and Aims

Optimal analgesia after total knee arthroplasty (TKA) enhances patients' and surgical outcomes. The study investigated the ultrasound-guided genicular nerve block versus the periarticular infiltration in TKA.

Methods

Eighty-eight patients aged above 50 years scheduled for unilateral TKA were randomised as: Group 1 received intraoperative periarticular infiltration (0.5 mL adrenaline [4.5 µg/mL], 20 mL bupivacaine 0.5% with 89.5 mL saline) and Group 2 received immediate postoperative genicular nerve block (15 mL bupivacaine 0.25% with 2.5 g/mL adrenaline). The postoperative morphine consumption was during the first two postoperative days the primary outcome. The secondary outcomes were time to rescue analgesia, pain scores and functional outcomes. The comparison between groups was performed using the Chi-square test, the Student's t-test and the Mann-Whitney U test, as appropriate.

Results

The postoperative morphine consumption during the first two postoperative days and pain scores at rest at 12 h postoperatively were less in Group 1 than in Group 2 (P < 0.001). Pain scores during movement on the first postoperative day were lower in the periarticular group than the genicular group at 6, 12 and 24 h (P < 0.001). At 18 h, pain scores were higher in the periarticular group than in the genicular group at rest and movement (P < 0.001). Quadriceps motor strength scores were comparable between groups (P > 0.05). The knee range of motion and time up and go test during both days showed a statistically significant difference in the periarticular group compared to the genicular group (P < 0.05).

Conclusion

Periarticular infiltration and genicular nerve block yield effective postoperative analgesia and functional outcomes after TKA without motor affection.

Pain management following simultaneous bilateral total knee arthroplasty: genicular nerve blockade versus periarticular injection

The aim of the present study was to investigate whether the analgesic solution prepared for periarticular injection (PAI) could be utilized as a genicular nerve blockade (GNB) agent in bilateral knee arthroplasty, and to assess the pain control efficacy of this approach in comparison with PAI. This was a retrospective cohort in which patients undergoing simultaneous bilateral total knee arthroplasty (TKA) were evaluated. Thirty patients were enrolled. The standard PAI was used for one knee, while the PAI solution was applied in the form of GNB to the other. Visual Analog Scale (VAS) pain scores were measured and recorded separately for each knee, at rest (static) and during exercise (dynamic). Active range of joint motion (JRM) for both knee joints was measured preoperatively, at postoperatively. Compared to the PAI group, the GNB group had lower VAS scores at 2 and 8 hours (p = 0.030 and p < 0.001, respectively). The GNB group also had lower dynamic VAS scores at 2, 8, and 24 hours (p = 0.009, p <0.001 and p<0.001, respectively). Static and dynamic VAS measurements did not demonstrate any differences between groups (GNB vs. PAI) at 48 hours and 30 days (p>0.05). When the reduction in VAS scores was assessed, we found that the decrease in both scores was significantly greater in the PAI group compared to the GNB group (p<0.001, for both). There were no significant differences between the groups with regard to drainage volume, complications and JRM (p>0.05). GNB was found to be more effective for pain control throughout the first postoperative day in patients who underwent simultaneous bilateral TKA.