Motor-sparing nerve blocks for total knee replacement: A scoping review

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.

Comparing Different Multimodal Analgesia Protocols for Primary Total Knee Arthroplasty-A Retrospective Cohort Analysis

Background: Several local regional anesthesia regimes have been described in the literature to reduce post-surgical pain following total knee arthroplasty (TKA), but it is unclear which regime has the best analgetic effect combined with the best motor function. The aim of this study was to determine if patients with infiltration between the popliteal artery and capsule of the posterior knee (IPACK) combined with an adductor canal block (SACB) had less pain, better motor function, and less opioid consumption after TKA than patients with a femoral nerve block (FNB) combined with a popliteal sciatic nerve block (PSB). Methods: In a retrospective cohort analysis, 342 patients following primary TKA were examined; 175 patients were treated with an IPACK combined with a SACB, and 167 patients with a femoral FNB combined with a PSB. The outcome parameters postoperative pain (visual analogue scale (VAS) for mobilization and at rest, functional recovery, opioid consumption, hospital discharge, and complications were analyzed and compared between both groups. Results: The IPACK/SACB group had a higher postoperative need for opioids despite higher doses of ropivacaine compared to the FNB/PSB group, accompanied by higher VAS scores. Patients' satisfaction was equal between the groups. Both groups showed comparable mobilization rates and walking distances following TKA. Conclusions: IPACK/SACB showed equal results compared to FNB/PSB for mobilization rates and patients' satisfaction following TKA without a reduction in opioid consumption.

Anesthesia for the Patient Undergoing Knee Procedures

Anesthesia for patients undergoing knee procedures encompasses a large patient population with significant variation in patient age, comorbidities, and type of surgery. In addition, these procedures are performed in vastly different surgical environments, including large academic hospitals, private hospitals, and out-patient surgical centers. These variabilities require a thoughtful and individualized anesthetic approach tailored toward the medical and surgical needs of each patient. This article discusses anesthetic approaches to patients with acute, subacute, and chronic knee-related pathology requiring surgery. We will also review pertinent knee anatomy and innervation and discuss regional nerve blocks and their applications to knee-related surgical procedures.

The minimum effective concentration (MEC90) of bupivacaine for an ultrasound-guided suprainguinal fascia iliaca compartment block for analgesia in knee surgery: a dose-finding study

BACKGROUND

In recent years, the suprainguinal fascia iliaca compartment block (SFICB) has become more common in clinical practice. This assessor-blinded dose-finding study aimed to determine the minimum effective concentration (MEC90, MEC95) of bupivacaine for a single-injection SFICB in patients undergoing arthroscopic anterior cruciate ligament repair.

METHODS

This prospective study was conducted at a tertiary hospital (postoperative recovery room and ward). The SFICB was performed as a postsurgical intervention after spinal anesthesia. Seventy patients were allocated using the biased-coin design up-and-down sequential method. The ultrasound-guided SFICB was performed using different bupivacaine concentrations, and standard multimodal analgesia was administered to all patients. Block success was defined as the absence of pain or presence of only tactile sensation during the pinprick test conducted on the anterior and lateral regions of the mid-thigh six hours postoperatively.

RESULTS

According to isotonic regression and bootstrap CIs, the MEC90 value of bupivacaine for a successful SFICB was 0.123% (95% CI [0.098, 0.191]) and the MEC95 value was 0.188% (95% CI [0.113, 0.223]).

CONCLUSIONS

Our study showed that the MEC90 and MEC95 values for bupivacaine administered via an SFICB for analgesia were 0.123% and 0.188%, respectively. One advantage of using lower concentrations of bupivacaine is the associated reduction in quadriceps weakness.

Comparison of Analgesic Effects of Continuous Femoral Nerve Block, Femoral Triangle Block, and Adductor Block After Total Knee Arthroplasty: A Randomized Clinical Trial

OBJECTIVES

This study aimed to compare the analgesic effects of continuous femoral nerve block (FNB), femoral triangle block (FTB), and adductor canal block (ACB) following total knee arthroplasty (TKA). The goal was to identify the most effective nerve block technique among these.

METHODS

Patients undergoing TKA were randomly assigned to 1 of 3 groups: FNB, FTB, or ACB. Nerve blocks were administered preoperatively, with catheters placed for patient-controlled nerve analgesia (PCNA). The primary end point was the Numeric Rating Scale (NRS) score at movement at 24 hours postsurgery. Secondary end points included NRS scores at rest and movement, quadriceps strength, Timed Up and Go (TUG) test performance, range of motion, effective PCNA utilization, and opioid consumption at various postsurgery time points.

RESULTS

Of the 94 valid data sets analyzed (FNB: 31, FTB: 31, ACB: 32), significant differences were observed in the primary end point (H=7.003, P =0.03). Post hoc analysis with Bonferroni correction showed that the FNB group had a significantly lower median pain score (3 [2 to 4]) compared with the ACB group (4 [3 to 5], Bonferroni-adjusted P =0.03). Regarding secondary end points, both the FNB and FTB groups had significantly lower NRS scores than the ACB group at various time points after surgery. Quadriceps strength and TUG completion were better in the FTB and ACB groups. There were no statistically significant differences among the groups for the other end points.

DISCUSSION

Continuous FTB provides postoperative analgesia comparable to FNB but with the advantage of significantly less impact on quadriceps muscle strength, a benefit not seen with FNB. Both FTB and ACB are effective in preserving quadriceps strength postoperatively.

Triple injection peri-sartorius (TIPS) block for postoperative analgesia after total knee arthroplasty: Randomised controlled study

Background and Aims

Motor-sparing analgesia after total knee arthroplasty (TKA) is crucial. The primary endpoint was the postoperative visual analogue scale (VAS) score after triple injection peri-sartorius (TIPS) block after TKA. Secondary endpoints were postoperative morphine consumption, 24-h postoperative ambulation distances and the degrees of active knee extension.

Methods

After general anaesthesia or spinal anaesthesia administration and before surgical incision, 80 patients undergoing TKA were randomised into group TIPS (received ultrasound-guided TIPS block where 40 ml 0.25% bupivacaine and 4 mg dexamethasone were injected: 10 ml at the distal femoral triangle, 10 ml above the sartorius and 20 ml at the distal adductor canal) and group FNB (femoral nerve block; received ultrasound-guided FNB with 20 ml 0.25% bupivacaine mixed with 4 mg dexamethasone). Postoperative pain score was noted and compared.

Results

Dynamic VAS scores were lower in the TIPS group than in FNB, while the resting VAS scores were not significantly different. Mean (standard deviation [SD]) postoperative morphine consumption was 5.82 (2.47) mg in the TIPS group (95% confidence interval [CI] 5.03,6.61) versus 9.87 (2.99) mg in the FNB group (95% CI 8.91,10.83). Ambulation distances and active postoperative knee extension in the TIPS group showed greater significance than in the FNB group (TIPS: 18.0 [7.37] m, 95% CI 15.64,20.35] vs. FNB: 8.95 [5.93] m, 95% CI 7.05,10.84) and (TIPS: 52.12 [16.39], 95% CI 46.88,57.33 vs. FNB: 26.05 [11.10], 95% CI 22.501,29.59). Nausea was more evident in FNB patients.

Conclusion

TIPS block provides superior analgesia than FNB with motor sparing of the quadriceps after TKA.

Comparison of Analgesic Efficacies of the iPACK (Interspace Between the Popliteal Artery and Capsule of the Posterior Knee) and Genicular Nerve Blocks Used in Combination With the Continuous Adductor Canal Block After Total Knee Arthroplasty: A Randomized Clinical Trial

BACKGROUND

The interspace between the popliteal artery and capsule of the posterior knee (iPACK) block and the genicular nerve block (GNB) are motor-sparing nerve blocks used for knee pain relief. We compared the analgesic efficacies of ultrasound-guided iPACK block and GNB when combined with continuous adductor canal block after total knee arthroplasty.

METHODS

In this randomized control study, 132 total knee arthroplasty patients were assigned to the iPACK, GNB, and iPACK + GNB groups. All patients received combined spinal anesthesia and continuous adductor canal block. The primary outcome was the 8-hour postoperative pain score during movement. Secondary outcomes were pain scores, posterior knee pain, intravenous morphine consumption, and tibial and common peroneal nerve sensorimotor function. All included patients completed the study.

RESULTS

The 4-hour and 8-hour postoperative pain scores during movement were significantly lower in the iPACK + GNB group than that in the iPACK group (-2.5 [3.6, 1.3]; P < .001 and -2 [-3, -1]; P < .001, respectively). The differences in rating pain scores and posterior knee pain were not clinically relevant. The iPACK group demonstrated a significantly higher intravenous morphine consumption than did the GNB and iPACK + GNB groups during the first 48 hours postoperatively (P < .001) but were not clinically relevant. There was no incidence of complete sensorimotor blockade in any of the groups.

CONCLUSION

The iPACK-GNB combination relieved pain during movement better than the iPACK block alone during the 8 hours postoperatively after total knee arthroplasty in setting of multimodal analgesia such as adductor canal block.

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

Genicular nerves block is a promising technique to treat acute postoperative pain in total knee arthroplasty. Similar to surgeon-administered local infiltration analgesia, it targets sensory branches from the knee capsule, but through a selective ultrasound-guided injection that reduces local anaesthetic dose (150 ml ropivacaine 0.2% with local infiltration analgesia vs. 20 ml with genicular nerves block). This randomised non-inferiority trial compared the analgesic efficacy of genicular nerves block vs. local infiltration analgesia in the first 24 h following total knee arthroplasty. Sixty patients were randomly allocated to receive either ultrasound-guided block of five genicular nerves or local infiltration analgesia. The primary outcome was rest pain numeric rating scale (0-10) at 24 h. Secondary outcomes included pain numeric rating scale (rest and movement) and cumulative opioid consumption during the first 24 h. We analysed 29 patients in the genicular nerves block group and 30 in the local infiltration analgesia group. We found that the median difference (95%CI) in postoperative rest pain at 24 h (non-inferiority criteria, Δ = 1) was -1.0 (-2.0 to 1.0, p < 0.001). Median difference in cumulative opioid consumption was 0.0 mg (-3.0-5.0, p < 0.001) meeting the non-inferiority criteria, Δ = 23 mg. We conclude that genicular nerves block of five nerves provides non-inferior analgesia in the first 24 h following surgery compared with local infiltration analgesia, but with a considerable reduction in the local anaesthetic dose.

Adductor Canal Block Combined with Interspace between the Popliteal Artery and Capsule of the Knee (iPACK) versus Periarticular Injection for Total Knee Arthroplasty

BACKGROUND

The combination of the adductor canal block (ACB) and the infiltration of anesthetic solution into the interspace between the popliteal artery and capsule of the knee (iPACK) has become increasingly used to augment rapid recovery protocols in total knee arthroplasty (TKA). However, its efficacy in comparison with periarticular anesthetic injection (PAI) alone has yet to be evaluated. Hence, we conducted a retrospective study to compare PAI and ACB + iPACK for controlling pain after TKA.

METHODS

Propensity scores, incorporating American Society of Anesthesiologists scores, body mass index, age, and sex, were used to match the ACB + iPACK group with the PAI group. All patients received the identical surgical technique and postoperative care. Outcome measures were visual analog scale (VAS) for pain, morphine consumption, knee flexion angle, straight leg raising (SLR), postoperative nausea vomiting (PONV), and length of stay (LOS) after the surgery.

RESULTS

After matching by propensity score, there were 49 patients with comparable demographic data in each group. The VAS and morphine requirements of the PAI and ACB + iPACK groups were not different during the first 48 hours after TKA. At 72 hours postoperatively, the VAS of the ACB + iPACK was 0.97 higher than that of the PAI group (p = 0.020). Knee flexion angle, SLR, PONV, and LOS were not significantly different between groups. No procedure-related complications were identified in either group.

CONCLUSIONS

The anesthesiologist-administered ACB + iPACK was as effective as surgeon-administered PAI in controlling pain in the first 48 hours after TKA. However, the ACB + iPACK group had higher intensity of pain than did the PAI group at 72 hours after TKA.

Analgesic efficacy of adding the IPACK block to multimodal analgesia protocol for primary total knee arthroplasty: a meta-analysis of randomized controlled trials

BACKGROUND

Total knee arthroplasty (TKA) is a standard treatment for end-stage degenerative knee disease. Most patients will experience moderate-to-severe postoperative knee pain, significantly affecting rehabilitation. However, controversy remains regarding the efficacy of adding the interspace between the popliteal artery and capsule of the knee (IPACK) into multimodal analgesia protocol.

METHODS

PubMed, Medline, Embase, Cochrane Library, and other databases were searched from inception to February 1, 2021. Studies comparing patients receiving IPACK to patients not receiving IPACK were included. The primary outcome was the ambulation pain score on a visual analogue scale (VAS) of 0-10. Secondary outcomes included pain score at rest, morphine usage, functional recovery, clinical outcomes, and complications.

RESULTS

Thirteen RCTs involving 1347 knees were included. IPACK was associated with lower ambulation pain scores (weight mean difference [WMD] - 0.49, 95% confidence interval [CI] - 0.72 to - 0.26). The benefits were observed from 2 to 4 h, 6 to 12 h, and beyond one week. IPACK also significantly reduced rest pain scores (WMD - 0.49, 95% CI - 0.74 to - 0.24), and the benefits were observed from 6 to 12 h and beyond one week. IPACK reduced the overall morphine consumption (WMD - 2.56, 95% CI - 4.63 to - 0.49). Subgroup analysis found reduced oral morphine consumption from 24 to 48 h (WMD - 2.98, 95% CI - 5.71 to - 0.24) and reduced rate of morphine requirement from 12 to 24 h (relative risk [RR] = 0.51, 95% CI 0.31 to 0.83). Functional recovery outcomes regarding ambulation distances (on the second postoperative day [POD2]) (WMD = 1.74, 95% CI 0.34 to 3.15) and quadriceps muscle strength (at 0 degree) (WMD = 0.41, 95% CI 0.04 to 0.77) favored IPACK. And IPACK reduced the rate of sleep disturbance (on POD 1) (RR = 0.39, 95% CI 0.19 to 0.81). There was no significant difference in the other outcomes.

CONCLUSIONS

Moderate-level evidence confirmed that IPACK was related to better results in pain scores, morphine usage, and functional recovery without increasing the risk of complications.

REGISTRATION

CRD42021252156.

The Ramifications of Opioid Utilization and Outcomes of Alternative Pain Control Strategies for Total Knee Arthroplasties

Morbidity and mortality related to opioid use has generated a public health crisis in the United States. Total knee arthroplasty (TKA) is an increasingly common procedure and is often accompanied by post-operative opioid utilization. Unfortunately, post-operative opioid usage after TKA has been shown to lead to higher rates of complications, longer hospital stays, increased costs, and more frequent need for revision surgery. Pre-operative opioid utilization has been shown to be one of the most important predictors of post-operative opioid usage. Additional risk factors for continued post-operative opioid utilization after TKA include pre-operative substance and tobacco use as well as higher post-operative prescription dosages, younger age, female gender, and Medicaid insurance. One method for mitigating excessive post-operative opioid utilization are Enhanced Recovery After Surgery (ERAS) protocols, which include a multidisciplinary approach that focuses on perioperative factors to optimize patient recovery and function after surgery. Additional strategies include multimodal pain regimens with epidural anesthetics, extended duration local anesthetics and adjuvants, and ultrasound guided peripheral nerve blocks. In recent years, opioid prescribing duration limitations have also been put into place by state and federal government, hospital systems, and ambulatory surgery centers making effective acute pain management imperative for all stakeholders. In this regard, as rates of TKA continue to increase across the United States, multidisciplinary efforts by all stakeholders are needed to ensure adequate pain control while preventing the negative sequalae of opioid medications.

Anesthesia for the Patient Undergoing Knee Procedures

Anesthesia for patients undergoing knee procedures encompasses a large patient population with significant variation in patient age, comorbidities, and type of surgery. In addition, these procedures are performed in vastly different surgical environments, including large academic hospitals, private hospitals, and out-patient surgical centers. These variabilities require a thoughtful and individualized anesthetic approach tailored toward the medical and surgical needs of each patient. This article discusses anesthetic approaches to patients with acute, subacute, and chronic knee-related pathology requiring surgery. We will also review pertinent knee anatomy and innervation and discuss regional nerve blocks and their applications to knee-related surgical procedures.

Additional Peripheral Nerve Block to Periarticular Injection Has No Benefit for Patients Undergoing TKA: A Factorial Propensity Score-Matched Analysis Comparing Four Multimodal Analgesic Techniques

BACKGROUND

Controversy remains over what and how many analgesic techniques are required as the most effective multimodal pain regimen in total knee arthroplasty (TKA). This study aimed to evaluate the effect of additional analgesic methods combined with periarticular injection (PAI) analgesia for TKA.

METHODS

Using retrospective cohort data, patients undergoing TKA with spinal anesthesia and PAI were divided into 4 groups. Group A (control) comprised 66 patients; group B (73 patients) had additional adductor canal block; group C (70 patients) obtained additional femoral nerve block, and group D (73 patients) received additional adductor canal block and intrathecal morphine. Propensity score matching was applied to compare visual analog scale (VAS) for pain intensity, cumulative morphine use (CMU), knee flexion angle, straight leg raise, length of hospital stay, and postoperative nausea and vomiting.

RESULTS

There was no significant difference regarding VAS and morphine use, when either group B or C was compared with group A. Group D had significantly lower VAS than groups A, B, and C during the first 24 hours after surgery and required significantly less CMU than groups A and B. However, the pain score of group D increased afterward, with significantly longer length of hospital stay than groups A and B. There was no difference in straight leg raise among the groups.

CONCLUSION

Additional peripheral nerve block to PAI provides no benefit for patients undergoing TKA. Adjuvant intrathecal morphine could significantly reduce the VAS and CMU in the acute postoperative period; however, rebound pain with prolonged hospital stays was observed.

Adductor canal block performed 20 hours after total knee arthroplasty to improve postoperative analgesia and functional recovery: a double-blind randomized controlled clinical trial

BACKGROUND

The goal of postoperative pain protocols in total knee arthroplasty (TKA) is to get pain free patients throughout severe pain period without impairing walking ability. The aim of the study was to investigate if an adductor canal block performed 20 hours after TKA, in patients treated with systemic analgesia and intraoperative local infiltration anaesthesia (LIA), improves postoperative pain and functional outcomes.

METHODS

A prospective randomized, double blinded controlled study was conducted. One hundred eighty-three patients undergoing primary TKA were randomized to receive either a sham block or an adductor canal block with 20 ml of ropivacaine 0.5%. The primary outcome was resting and dynamic pain scores using the numerical pain rating scale (NPRS). Secondary outcomes included opioid rescue requirements, quadriceps and adductor muscle strength, patient ability for ambulation and complications.

RESULTS

Two hours after the block, in adductor canal block group NPRS was significantly lower at rest (1[0-2] vs. 3[2-5], P<0.001) and with mobilization (5[3-6] vs. 6[5-8], P<0.001), and quadriceps strength was significantly higher (3.7[2.7-6] vs. 3(1.7-4.9), P=0.023). The differences were not maintained beyond 24 hours post-block. In the first 24 hours the percentage of patients with tramadol requirements was lower in the adductor canal block group (36[38.3] vs 52[58,4], P =0.006). Other secondary outcomes were similar between groups. There were no patient falls.

CONCLUSIONS

An adductor canal block done 20 hours after total knee arthroplasty reduces pain and opioid requirements without increasing the risk of falls. An optimal pain control, especially at movement was not achieved.

Ultrasound-guided genicular nerve blocks following total knee arthroplasty: a randomized, double-blind, placebo-controlled trial

INTRODUCTION

Local anesthetic blockade of the genicular nerves, known targets of radiofrequency ablative techniques for knee pain, has not previously been studied in a randomized controlled trial evaluating acute pain after knee arthroplasty. We hypothesized that genicular nerve blockade added to an existing block regimen in total knee arthroplasty would result in a reduction in 24 hours opioid consumption.

METHODS

Patients (American Society of Anesthesiologists 1-3, aged 18-85 years) undergoing primary total knee arthroplasty were randomized to receive single-injection nerve blocks of the superolateral, superomedial, and inferomedial genicular nerves with injectate (15 mL 0.25% bupivacaine and 2 mg dexamethasone or 15 mL saline placebo). All subjects received a standard oral analgesic regimen, spinal anesthetic with 12.5 mg isobaric bupivacaine, infiltration between the popliteal artery and capsule of the knee with 0.2% ropivacaine, and postoperative adductor canal perineural infusion with 0.2% ropivacaine. The primary outcome was 24 hours opioid consumption (measured in morphine milliequivalents).

RESULTS

Forty (40) subjects were enrolled. Opioid consumption at 24 hours was significantly lower in the BLOCK group compared with the SHAM group (23±20 vs 58±35, p<0.001), and this difference remained significant at 48 hours (50±40 vs 98±56, p=0.004). Pain scores were reduced in the BLOCK group at time 6 hours (2.6±1.9 vs 4.3±2.2, p=0.012), but were otherwise similar at remaining time points. Patient satisfaction at 24 hours and 20 m walk test times were similar between groups.

DISCUSSION

Genicular nerve blockade was associated with a reduction in opioid consumption at 24 hours in primary total knee arthroplasty patients.

TRIAL REGISTRATION NUMBER

NCT03706313.