The relative analgesic value of a femoral nerve block versus adductor canal block following total knee arthroplasty: a randomized, controlled, double-blinded study

[Comparison of the effects of sciatic nerve block combined with continuted femoral nerve block or continuted adductor canal block on pain and motor function after total knee arthroplasty]

Objective

To compare the effect of sciatic nerve block (SNB) combined with continuted femoral nerve block (FNB) or continuted adductor canal block (ACB) on pain and motor function after total knee arthroplasty (TKA).

Methods

A total of 60 patients with TKA-treated osteoarthritis of the knee who met the selection criteria were enrolled between November 2020 and February 2021 and randomised allocated into the study group (SNB combined with continuted ACB) and the control group (SNB combined with continuted FNB), with 30 cases in each group. There was no significant difference in gender, age, body mass, height, body mass index, preoperative Hospital for Special Surgery (HSS) score, femoral tibial angle, and medial proximal tibial angle between the two groups ( P>0.05). The operation time, the initial time to the ground, the initial walking distance, and the postoperative hospital stay were recorded. At 2, 4, 6, 12, 24, and 48 hours after operation, the numerical rating scale (NRS) score was used to evaluate the rest pain around the knee joint, the quadriceps femoris muscle strength was evaluated by the freehand muscle strength method, and the knee flexion and extension angles were measured.

Results

There was no significant difference in the operation time and initial walking distance between the two groups ( P>0.05); the initial time to the ground and postoperative hospital stay of the study group were significantly shorter than those of the control group ( P<0.05). Except for the 48-hour postoperative NRS score of the study group, which was significantly lower than that of the control group ( P<0.05), there was no significant difference in the NRS scores between the two groups at the remaining time points ( P>0.05). The quadriceps femoris muscle strength from 4 to 24 hours postoperatively and the knee extension angle from 2 to 6 hours postoperatively of the study group were significantly better than those of the control group ( P<0.05); the differences in the quadriceps femoris muscle strength and knee extension and flexion angles between the two groups at the remaining time points were not significant ( P>0.05).

Conclusion

SNB combined with either continuted ACB or continuted FNB can effectively relieve pain in patients after TKA, and compared with combined continuted FNB, combined continuted ACB has less effect on quadriceps femoris muscle strength, and patients have better recovery of knee flexion and extension mobility.

Ambulatory total hip and knee arthroplasty: a literature review and perioperative considerations

PURPOSE

Total joint arthroplasty (TJA), particularly for the hip and knee, is one of the most commonly performed surgical procedures. The advancement/evolution of surgical and anesthesia techniques have allowed TJA to be performed on an ambulatory/same-day discharge basis. In this Continuing Professional Development module, we synthesize the perioperative evidence that may aid the development of successful ambulatory TJA pathways.

SOURCE

We searched MEDLINE, Embase, CENTRAL, and the Cochrane Database of Systematic Reviews for ambulatory or fast-track TJA articles. In the absence of direct evidence for the ambulatory setting, we extrapolated the evidence from the in-patient TJA literature.

PRINCIPAL FINDINGS

Patient selection encompassing patient, medical, and social factors is fundamental for successful same-day discharge of patients following TJA. Evidence for the type of intraoperative anesthesia favours neuraxial technique for achieving same day discharge criteria and reduced perioperative complications. Availability of short-acting local anesthetic for neuraxial anesthesia would affect the anesthetic choice. Nonetheless, modern general anesthesia with multimodal analgesia and antithrombotics in a well selected population can be considered. Regional analgesia forms an integral part of the multimodal analgesia regime to reduce opioid consumption and facilitate same-day hospital discharge, reducing hospital readmission. For ambulatory total knee arthroplasty, a combination of adductor canal block with local anesthetic periarticular infiltration provided is a suitable regional analgesic regimen.

CONCLUSION

Anesthesia for TJA has evolved as such that same-day discharge will become the norm for selected patients. It is essential to establish pathways for early discharge to prevent adverse effects and readmission in this population. As more data are generated from an increased volume of ambulatory TJA, more robust evidence will emerge for the ideal anesthetic components to optimize outcomes.

Periarticular injection, iPACK block, and peripheral nerve block in pain management after total knee arthroplasty: a structured narrative review

INTRODUCTION

Total knee arthroplasty (TKA) is commonly performed in patients with end-stage osteoarthritis or rheumatoid arthritis of the knee to reduce joint pain, increase mobility, and improve quality of life. However, TKA is associated with moderate to severe postoperative pain, which remains a significant clinical challenge. Surgeon-administered PAI and anesthesiologist-administered iPACK have proven viable alternatives to conventional peripheral nerve blocks. This review aims to discuss which IPACK block or periarticular injection, combined or not with different peripheral nerve blocks, has better effects on postoperative rehabilitation, patient satisfaction, and overall outcome.

MATERIAL AND METHODS

The literature review was performed on standards of care, current therapeutic options, a pain management protocol, and innovative treatment options for patients undergoing total knee arthroplasty. The literature was reviewed through four electronic databases: PubMed, Cochrane Library, Google Scholar, and Embase.

RESULTS

The initial search yielded 694 articles. Fifty relevant articles were selected based on relevance, recentness, search quality, and citations. Six studies compared PAI to peripheral nerve block (PNB), and eight studies checked the effectiveness of adding PNB to PAI. Three studies compared iPACK to PNB, and ten reviewed the point of adding PNB to iPACK.

CONCLUSIONS

The literature review indicates that the best analgesic effect is obtained by combining PAI or iPACK with a peripheral nerve block, particularly with ACB, due to its analgesic, motor-sparing effect, and satisfactory analgesia.

Single-injection nerve blocks for total knee arthroplasty: femoral nerve block versus femoral triangle block versus adductor canal block-a randomized controlled double-blinded trial

INTRODUCTION

Femoral nerve block (FNB) is a well-established analgesic technique for TKA. However, it associates quadriceps weakness. Therefore, femoral triangle block (FTB) and adductor canal block (ACB) were proposed as effective alternative motor-spearing techniques. The primary objective was to compare quadriceps muscle strength preservation between FNB, FTB and ACB in TKA. The secondary objective was to analyze pain control and functional outcomes.

METHODS

This is a prospective, double-blinded RCT. From April 2018 to April 2019, patients who undergo a primary TKA were randomized into three experimental groups: FNB-G1/FTB-G2/ACB-G3. Quadriceps strength preservation was measured as the difference in maximum voluntary isometric contraction (MVIC) preoperatively and postoperatively.

RESULTS

Seventy-eight patients (G1, n = 22; G2, n = 26; G3, n = 30) met our inclusion/exclusion criteria. Patients with FNB retained significantly lower baseline MVIC at 6 h postoperatively (p = 0.001), but there were no differences at 24 and 48 h. There were no differences between the groups in functional outcomes at any time point. Patients in the FNB-G1 presented significant lower pain scores at 6 h (p = 0.01), 24 h (p = 0.005) and 48 h (p = 0.01). The highest cumulative opioid requirement was reported in ACB-G3.

CONCLUSION

For patients undergoing TKA, FTB and ACB preserve quadriceps strength better than FNB at 6 h postoperatively, but there are no differences at 24 and 48 h. Moreover, this early inferiority does not translate to worse functional outcomes at any time point. FNB is associated with better pain control at 6, 24 and 48 h after surgery, while ACB presents the highest cumulative opioid requirement.

CLINICAL TRIAL REGISTRATION

This study was registered in clinicaltrials.gov (NCT03518450; https://clinicaltrials.gov/ct2/show/NCT03518450 ; submitted March 17, 2018).

Anatomical and Radiological Assessments of Injectate Spread Stratified by the Volume of the Pericapsular Nerve Group Block

BACKGROUND

The pericapsular nerve group (PENG) block was recently suggested as a regional technique for managing acute pain after hip surgery. However, few anatomical studies have confirmed the spread of injectate during the PENG block. This cadaver study aimed to analyze injectate spread to the target nerves during single-injection ultrasound-guided PENG block.

METHODS

Ultrasound-guided PENG block with 3 different injectate volumes (10, 20, or 30 mL) was performed in 18 cadavers. Injectate spread by the volume was first evaluated on computed tomography, followed by cadaver dissection. The spread of the dye over the pelvis and lower limb was evaluated.

RESULTS

The articular branches of the femoral nerve were stained nearly sufficiently with 20- and 30-mL specimens. The femoral nerve itself was stained simultaneously in six of 12 (50%) 20-mL specimens and 12 of 12 (100%) 30-mL specimens. The accessory obturator nerve was observed only in three (9%) of 36 specimens. The articular branches of the obturator nerve were rarely affected, regardless of injectate volume (1/12, 10 mL specimens; 2/12, 20 mL specimens; 1/12, 30 mL specimens; P > .999). Rather, the obturator nerve was affected. However, the obturator nerve was not stained consistently even with 30 mL of injectate (50%).

CONCLUSIONS

After combining the dissection and radiological findings, the single-injection ultrasound-guided PENG blocks with volumes of 10, 20, and 30 mL do not support motor sparing or selective anterior hip capsule innervation in a clinical setting. If early rehabilitation is needed, high-volume PENG block might not be the ideal option, and persisting pain after PENG block might be attributed in part to the lack of obturator nerve articular branches blockade.

Pro and Con: How Important Is the Exact Location of Adductor Canal and Femoral Triangle Blocks?

In this Pro-Con commentary article, we debate the importance of anterior thigh block locations for analgesia following total knee arthroplasty. The debate is based on the current literature, our understanding of the relevant anatomy, and a clinical perspective. We review the anatomy of the different fascial compartments, the course of different nerves with respect to the fascia, and the anatomy of the nerve supply to the knee joint. The Pro side of the debate supports the view that more distal block locations in the anterior thigh increase the risk of excluding the medial and intermediate cutaneous nerves of the thigh and the nerve to the vastus medialis, while increasing the risk of spread to the popliteal fossa, making distal femoral triangle block the preferred location. The Con side of the debate adopts the view that while the exact location of local anesthetic injection appears anatomically important, it has not been proven to be clinically relevant.

Motor-Sparing Effect of Adductor Canal Block for Knee Analgesia: An Updated Review and a Subgroup Analysis of Randomized Controlled Trials Based on a Corrected Classification System

OBJECTIVE

Discrepancies in the definition of adductor canal block (ACB) lead to inconsistent results. To investigate the actual analgesic and motor-sparing effects of ACB by anatomically defining femoral triangle block (FTB), proximal ACB (p-ACB), and distal ACB (d-ACB), we re-classified the previously claimed ACB approaches according to the ultrasound findings or descriptions in the corresponding published articles. A meta-analysis with subsequent subgroup analyses based on these corrected results was performed to examine the true impact of ACB on its analgesic effect and motor function (quadriceps muscle strength or mobilization ability). An optimal ACB technique was also suggested based on an updated review of evidence and ultrasound anatomy.

MATERIALS AND METHODS

We systematically searched studies describing the use of ACB for knee surgery. Cochrane Library, PubMed, Web of Science, and Embase were searched with the exclusion of non-English articles from inception to 28 February 2022. The motor-sparing and analgesic aspects in true ACB were evaluated using meta-analyses with subsequent subgroup analyses according to the corrected classification system.

RESULTS

The meta-analysis includes 19 randomized controlled trials. Compared with the femoral nerve block group, the quadriceps muscle strength (standardized mean difference (SMD) = 0.33, 95%-CI [0.01; 0.65]) and mobilization ability (SMD = -22.44, 95%-CI [-35.37; -9.51]) are more preserved in the mixed ACB group at 24 h after knee surgery. Compared with the true ACB group, the FTB group (SMD = 5.59, 95%-CI [3.44; 8.46]) has a significantly decreased mobilization ability at 24 h after knee surgery.

CONCLUSION

By using the corrected classification system, we proved the motor-sparing effect of true ACB compared to FTB. According to the updated ultrasound anatomy, we suggested proximal ACB to be the analgesic technique of choice for knee surgery. Although a single-shot ACB is limited in duration, it remains the candidate of the analgesic standard for knee surgery on postoperative day 1 or 2 because it induces analgesia with less motor involvement in the era of multimodal analgesia. Furthermore, data from the corrected classification system may provide the basis for future research.

Adductor Canal Blocks Are Not Associated With Improved Early Postoperative Outcomes in Patients Undergoing Total Knee Arthroplasty

Background: As length of stay after total knee arthroplasty (TKA) continues to shorten, interventions that may reduce early postoperative pain and complications must be studied. Peripheral nerve block is being explored as a potential means of improving pain management. The purpose of this study was to evaluate the impact of adductor canal block (ACB) on postoperative outcomes for patients undergoing TKA. Methods: We conducted a retrospective review of 565 patients who received unilateral TKA under spinal anesthesia with a periarticular anesthetic injection. Patients were divided by ACB status. Univariate comparisons and multivariate regression were used to compare outcomes for patients receiving ACBs vs those who did not. Results: Of the 565 patients, 167 received an ACB, and 398 did not. Patients who received an ACB were less likely to require nausea medication during the immediate postoperative period. Length of stay, narcotic consumption, rate of discharge to home, postanesthesia care unit recovery time, urinary retention, ability to complete physical therapy, and 30-day readmission rate did not differ significantly between groups. After risk adjustment, the only significant finding was decreased likelihood of nausea in patients receiving an ACB. Conclusion: ACBs appear to have little to no significant impact on early clinical outcomes in patients having TKA under spinal anesthesia with a periarticular anesthetic injection. Further study of larger patient cohorts is required to validate these findings.

Early Postoperative Pain Control and Inflammation for Total Knee Arthroplasty: A Retrospective Comparison of Continuous Adductor Canal Block versus Single-Shot Adductor Canal Block Combined with Patient-Controlled Intravenous Analgesia

Objective

The aim of this study was to compare pain control and inflammation among patients who received a continuous adductor canal block (CACB) versus single-shot adductor canal block (SACB) combined with patient-controlled intravenous analgesia (PCIA) for total knee arthroplasty (TKA) analgesia in the first two days after surgery.

Design

Matched cohort retrospective study. Setting. University hospital. Patients. One hundred fifty-six patient charts were included in this study: 78 patients with CACB in Group A and 78 patients with SACB combined with PCIA in Group B. Patients were matched according to age, body mass index, and American Society of Anesthesiologists class. Measurements. The primary outcome of the study was Visual Analogue Scale (VAS) pain scores before operation (Pre) and at postoperative 6 (POH6), 12 (POH12), 24 (POH24), 30 (POH30), 36 (POH36), and 48 hours (POH48). Secondary outcomes included patient-controlled bolus, time of first postoperative ambulation, range of knee flexion and extension, inflammation cytokines on Pre and POH48, percentage of remedial analgesics treatment, incidence of adverse events and complications, hospital stay and cost, and Numerical Rating Scale (NRS) satisfaction scores at discharge. Main Results. Mean VAS scores at rest and with motion were lower in Group B than in Group A on all postoperative hours. At POH30, compared with Group A (1.1 ± 0.6), mean VAS scores at rest in Group B (0.9 ± 0.4) were lower (P=0.048), and compared with Group A (2.6 ± 0.7), mean VAS scores with motion in Group B (2.2 ± 0.8) were lower (P=0.001). The number of patient-controlled bolus was 4.3 ± 1.6 (95% CI 3.9-4.6) in Group A and 3.1 ± 1.3 (95% CI 2.8-3.4) in Group B, respectively (P < 0.001). Patients in Group B displayed better functional recovery and inflammation results at POH48 than Group A with respect to range of knee flexion and extension (117.8 ± 10.9° vs. 125.2 ± 9.4°, P < 0.001) and inflammation cytokines, including erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and interleukin-6 (IL-6) ((43.8 ± 16.1) vs. (36.8 ± 13.2), P=0.003; (34.9 ± 9.4 mg/L) vs. (29.6 ± 10.6 mg/L), P=0.001; (21.3 ± 8.7 pg/ml) vs. (14.0 ± 7.0 pg/ml), P < 0.001)).

Conclusion

SACB combined with PCIA in the first two days of patients undergoing TKA has better analgesic and beneficial effects on functional recovery and inflammation.

Transparency considerations for describing statistical analyses in research

Researchers who use the results of statistical analyses to draw conclusions about collected data must write a statistical analysis section in their manuscript. Describing statistical analyses in precise detail is as important as presenting the dosages of drugs and methodology of interventions. It is also essential for scientific accuracy and transparency in scientific research. We evaluated the quality of the statistical analysis sections of clinical research articles published in the Korean Journal of Anesthesiology between February 2020 and February 2021. Using a Likert scale where 1, 2, and 3 represented “not described at all,” “partially described,” and “fully described,” respectively, the following 6 items were assessed: 1) stating of the statistical analysis methods used, 2) rationale for and detailed description of the statistical analysis methods used, 3) parameters derived from the statistical analyses, 4) type and version of the statistical software package used, 5) significance level, and 6) sidedness of the test (one-sided vs. two-sided). The first 3 items evaluate issues directly related to the statistical analysis methods used and last 3 are indirectly related items. In all the included articles, the statistical analysis methods used were stated (score of 3). However, only 4 articles (12.9%) fully described the sidedness of the test (score of 3). Authors tend not to describe the sidedness of statistical analysis tests in the methodology section of clinical research articles. It is essential that the sidedness be described in research studies.

Evaluation of ultrasound-guided adductor canal block with two different concentration of bupivacaine in arthroscopic knee surgery: A feasibility study

STUDY OBJECTIVE

The application of regional anaesthesia techniques as a component of multimodal analgesia in knee arthroscopic surgeries increases the quality of postoperative analgesia. Adductor canal block (ACB) is an effective "motor sparing" analgesia technique used in knee surgeries. This study aimed to evaluate the efficacy of ACB using two different concentrations of local anaesthetic in terms of analgesic requirements and pain density in patients undergoing knee arthroscopy.

DESIGN

Prospective, randomised, controlled.

SETTING

Tertiary hospital.

PATIENTS

A total of 60 patients (ASA I-II) were evaluated in three groups, with 20 patients in each group.

INTERVENTIONS

Standardised postoperative analgesia was performed in all groups. In addition, ultrasound-guided ACB (same volume/two different concentrations of bupivacaine: 0.25% vs 0.16%) was applied to the experimental groups.

MEASUREMENTS

Tramadol consumption, rescue analgesic requirement and Numeric Rating Scores (NRS).

MAIN RESULTS

Tramadol requirement in the first 24 hours was significantly higher in the control group (209.5 ± 23.27 mg) (P < .001), and there was no difference between the experimental groups (63 ± 42.06 mg vs 80.5 ± 36.63 mg). Although the mean NRS scores in the first three hours were higher in the control group when compared with both block groups, it was similar in all groups in the following measurements.

CONCLUSION

In arthroscopic knee surgery, ACB interventions with 0.25% and 0.16% concentrations of bupivacaine were similar in terms of postoperative analgesic efficacy, and they increased the quality of multimodal analgesics when compared with the control group.

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.

The role of the iliotibial band cross-sectional area as a morphological parameter of the iliotibial band friction syndrome: a retrospective pilot study

Background

Iliotibial band friction syndrome (ITBFS) is a common disorder of the lateral knee. Previous research has reported that the iliotibial band (ITB) thickness (ITBT) is correlated with ITBFS, and ITBT has been considered to be a key morphologic parameter of ITBFS. However, the thickness is different from inflammatory hypertrophy. Thus, we made the ITB cross-sectional area (ITBCSA) a new morphological parameter to assess ITBFS.

Methods

Forty-three patients with ITBFS group and from 43 normal group who underwent T1W magnetic resonance imaging were enrolled. The ITBCSA was measured as the cross-sectional area of the ITB that was most hypertrophied in the magnetic resonance axial images. The ITBT was measured as the thickest site of ITB.

Results

The mean ITBCSA was 25.24 ± 6.59 mm² in the normal group and 38.75 ± 9.11 mm² in the ITBFS group. The mean ITBT was 1.94 ± 0.41 mm in the normal group and 2.62 ± 0.46 mm in the ITBFS group. Patients in ITBFS group had significantly higher ITBCSA (P < 0.001) and ITBT (P < 0.001) than the normal group. A receiver operator characteristic curve analysis demonstrated that the best cut-off value of the ITBT was 2.29 mm, with 76.7% sensitivity, 79.1% specificity, and area under the curve (AUC) 0.88. The optimal cut-off score of the ITBCSA was 30.66 mm², with 79.1% sensitivity, 79.1% specificity, and AUC 0.87.

Conclusions

ITBCSA is a new and sensitive morphological parameter for diagnosing ITBFS, and may even be more accurate than ITBT.

A Low Dose of Naloxone Added to Ropivacaine Prolongs Femoral Nerve Blockade: A Randomized Clinical Trial

Femoral nerve blocks (FNBs) are used as safe and useful procedures to control severe postoperative pain from total knee arthroplasty (TKA). Various adjuvants have been used to prolong the duration of the local anesthetic blockade. This study evaluated whether a low dose of naloxone administered with local anesthetics prolongs the duration of FNB. A prospective, randomized double-blind controlled study was conducted with 74 patients undergoing unilateral TKA. Through a single-bolus administration guided by ultrasound, the control group (group C) received 20 mL of 0.375% ropivacaine, while the naloxone group (group N) received 20 mL of 0.375% ropivacaine with 100 ng of naloxone. The time elapsed before the first analgesia request, the total amount of opioids consumed at 24 h postoperatively, the onset time of the sensory blockade, the visual analog pain scale (VAS) scores after arriving at the recovery room, after 6, 12, 18, and 24 h at rest and after 12, 18, and 24 h of activity, the quadricep strength before the FNB procedure and at 12 and 24 h postoperatively, the quality of sleep on the first night after surgery, the satisfaction score, and the incidence of postoperative complications were recorded. The time elapsed before the first analgesia request was significantly longer in group N (735.5 ± 187.2 min) than that in group C (602.6 ± 210.4 min) (P=0.003). The total dose of supplementary opioids consumed at 24 h postoperatively was significantly lower in group N (312.4 ± 141.7 μg) than that in group C (456.5 ± 279.5 μg) (P=0.007). Lower VAS scores were recorded in group N than that in group C at rest and during knee activity (rest, 12 h, P=0.001, 18 h, P=0.043; activity, 12 h, P=0.001). The addition of a low dose of naloxone to ropivacaine for FNB significantly delayed the first request for rescue analgesia and decreased the opioid consumption within 24 h, without significant complications.