Continuous adductor canal block is a better choice compared to single shot after primary total knee arthroplasty: A meta-analysis of randomized controlled trials

Analgesic Effect of Intermittent Multiple IPACK Block Combined with ACB in Patients with Flexion Contracture Knee Arthritis Undergoing Total Knee Arthroplasty

We aimed to compare the analgesic effects of intermittent multiple infiltrations between the popliteal artery and capsule of the posterior knee (IPACK) combined with adductor canal block (ACB) and intermittent ACB alone in patients with flexion contracture knee arthritis undergoing total knee arthroplasty (TKA). Forty-six patients who underwent elective unilateral TKA were divided into two groups (n = 23 each): intermittent multiple IPACK combined with ACB (group IA) and intermittent multiple ACB (group A). ACB was performed with 20 mL of 0.375% ropivacaine in each group and IPACK with 20 mL of 0.25% ropivacaine in group IA. Intermittent multiple nerve blocks were used for postoperative analgesia (IPACK block combined with ACB in group IA and ACB in group A between 7:30 and 8:30 a.m. on postoperative day 1 [POD1] and postoperative day 2 [POD2]). Primary outcomes assessed were pain at rest, motion-evoked pain (MEP), and range of motion (ROM) on POD1 and POD2. Secondary outcomes included opioid consumption, first ambulation time, ambulation distance, and postoperative complications. We observed that compared with group A, MEP decreased, ROM became wider, ambulation distance was longer, and opioid consumption decreased in group IA. Other outcomes were either similar between the groups or showed clinically insignificant differences. We conclude that multiple intermittent IPACK therapy combined with ACB provides superior analgesia than multiple intermittent ACB therapy alone in patients with flexion contracture knee arthritis undergoing TKA.

Peripheral Nerve Block Utilization is Associated With Decreased Postoperative Opioid Consumption and Shorter Length of Stay Following Total Knee Arthroplasty

Background

This study aims to examine differences in postoperative complications and opioid consumption associated with perioperative peripheral nerve block (PNB) utilization during primary total knee arthroplasty (TKA).

Methods

The Premier Healthcare Database was queried for adult patients who underwent primary, elective TKA from 2015 to 2020. Patients who received a femoral or adductor canal PNB were compared to patients who did not. PNB utilization was trended from 2015 to 2020. Univariate and multivariate regression analyses were performed to assess differences in the 90-day risk of postoperative complications between groups. The average inpatient opioid consumption in morphine milligram equivalents was assessed as a function of length of stay.

Results

Overall, 609,991 patients were included. PNB utilization increased from 9.29% in 2015 to 30.3% in 2020. After controlling for confounders, the PNB cohort was more likely to have same-day discharge (adjusted odds ratio [aOR] 1.88) and had a decreased risk of periprosthetic joint infection (aOR 0.87), pulmonary embolism (aOR 0.81), and respiratory failure (aOR 0.78). However, there was an increased risk of seroma (aOR 1.75) and hematoma (aOR 1.22) associated with PNB utilization. Lower average overall opioid exposure was seen in the PNB cohort vs no-PNB cohort (82.1 ± 194.7 vs 89.4 ± 214.1 morphine milligram equivalents, P < .001).

Conclusions

PNB utilization during primary TKA is associated with a shorter length of stay and decreased risk of multiple postoperative complications, as well as reduced postoperative opioid consumption. These data provide evidence in support of the safety and efficacy of this emerging practice. However, the clinical relevance of an increased risk of seroma and hematoma formation may warrant further investigation.

Does the Addition of iPACK Block to Adductor Canal Block Provide Improved Analgesic Effect in Total Knee Arthroplasty? A Systematic Review and Meta-Analysis

The interspace between popliteal artery and the capsule of posterior knee (iPACK) block was proposed in recent years to relieve posterior knee pain. Since adductor canal block (ACB) and iPACK involve different branches of the sensory nerves, it is theoretically feasible to combine iPACK block and ACB to relief pain after total knee arthroplasty (TKA). We aim to validate the efficacy of adding iPACK block to ACB in the setting of a multimodal pain management protocol following TKA. A comprehensive literature review on Web of Science, Embase, the Cochrane Library, and PubMed was performed. Eight studies (N = 1,056) that compared the efficacy of iPACK block + ACB with ACB alone were included. Primary outcomes consisted of Visual Analogue Scale (VAS) score at rest or during activity at various time points. Secondary outcomes include opioids consumption, walking distance, and length of hospital stay (LOS). Compared to ACB alone, VAS scores at rest (standardized mean difference [SMD]: -1.18; 95% confidence interval [CI]: -2.05 to -0.30) and during activity (SMD: -0.26; 95% CI: -0.49 to -0.03) on the day of surgery were lower in the iPACK block + ACB group. However, the difference did not reach the minimal clinically important difference. Opioids consumption at postoperative 24 hours was lower in the iPACK + ACB group (SMD: -0.295; 95% CI: -0.543 to -0.048). VAS score on postoperative day (POD) 1 and POD2, opioids consumption from 24 to 48 hours, walking distance, and LOS were not different. In conclusion, the addition of iPACK block to ACB in a multimodal pain management protocol can effectively reduce opioids consumption in the early postoperative period. This is a level III, meta-analysis study.

Analgesic benefits of single-shot versus continuous adductor canal block for total knee arthroplasty: a systemic review and meta-analysis of randomized trials

BACKGROUND

Adductor canal block (ACB) can provide important analgesic benefits following total knee arthroplasty (TKA), however, the extent to which these benefits can be enhanced or prolonged by a continuous catheter-based infusion compared with a single-shot injection of local anesthetic is unclear.

OBJECTIVES

This systematic review and meta-analysis (PROSPERO: CRD42021292738) review sought to compare the analgesic effectiveness of single shot to continuous ACB following TKA.

EVIDENCE REVIEW

We sought randomized trials from the US National Library of Medicine database (MEDLINE), Excerpta Medica database (EMBASE), and Cochrane Database of Systematic Reviews from inception to November 1, 2021, that compared single-shot to continuous ACB in adult patients undergoing TKA. The primary outcomes were (1) area under the curve (AUC) pain severity at rest and (2) cumulative opioid (oral morphine equivalent) consumption during the first 48 hours postoperatively. Secondary outcomes included postoperative pain severity scores up to 48 hours, cumulative opioid consumption at 24 hours, functional recovery, opioid-related side effects, and block-related complications. Risk of bias of included studies was assessed using the Cochrane risk of bias tool. Statistical pooling was conducted using the Hartung-Knapp-Sidik-Jonkman method for random effects. No funding was obtained for this review.

FINDINGS

Eleven trials (1185 patients) were included. No differences were observed in rest pain severity (AUC) or cumulative opioid consumption up to 48 hours postoperatively. In addition, no differences were observed in individual postoperative rest pain scores in the recovery room and at 12 and 24 hours, or in cumulative opioid consumption at 24 hours, functional recovery, and opioid-related side effects. Finally, fewer block-related complications were observed with single-shot ACB, with an OR (95% CI) of 0.24 (0.14 to 0.41) (p=0.002).

CONCLUSIONS

Our results suggest that continuous catheter-based ACB does not enhance or prolong the analgesic benefits when compared with single-shot ACB for TKA over the first 48 hours postoperatively. Overall, the results of our meta-analysis do not support the routine use of continuous ACB for postoperative analgesia after TKA.

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.

Continuous vs. single-shot adductor canal block for pain management following primary total knee arthroplasty: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Adductor canal block (ACB) provides effective analgesia following total knee arthroplasty (TKA). This systematic review aimed to compare continuous and single-shot ACB for pain management and functional recovery following TKA.

METHODS

MEDLINE, Embase, Web of Science and CENTRAL were searched up to January 5th, 2021. Included studies were randomized controlled trials comparing continuous to single-shot ACB for postoperative pain management after primary TKA. Primary outcome was opioid consumption and secondary outcomes were pain intensity, quadriceps strength, mobility, complications, and length of hospital stay. Meta-analyses were performed using random-effects method.

RESULTS

Eleven studies (910 patients) were included in this systematic review. Continuous ACB did not significantly decrease opioid consumption (8 studies; 642 patients; MD=-5.67; 95% CI: -13.87 to 2.54; I²=13%) but significantly decreased 48hours pain scores (10 studies; 852 patients; MD=-0,73; 95% CI: -0.93 to -0.54; I²=54%). Continuous ACB improved quadriceps strength (4 studies; 250 patients; SMD=0.59; 95% CI: 0.16 to 1.03; I²=63%) but not Timed Up and Go test performance (5 studies; 524 patients; MD=3.99; 95% CI: -8.98 to 1.01; I²=89%). Type of ACB did not affect nausea and vomiting (5 studies; 357 patients; RR=1.23; 95% CI: 0.65 to 2.34; I²=0%) nor length of hospital stay (8 studies; 655 patients; MD=-0.13; 95% CI: -0.28 to 0.01; I²=36%).

CONCLUSION

Continuous ACB did not reduce opioid consumption following TKA. Larger trials are required.

Pain management after total knee arthroplasty: PROcedure SPEcific Postoperative Pain ManagemenT recommendations

BACKGROUND

The PROSPECT (PROcedure SPEcific Postoperative Pain ManagemenT) Working Group is a global collaboration of surgeons and anaesthesiologists formulating procedure-specific recommendations for pain management after common operations. Total knee arthroplasty (TKA) is associated with significant postoperative pain that is difficult to treat. Nevertheless, pain control is essential for rehabilitation and to enhance recovery.

OBJECTIVE

To evaluate the available literature and develop recommendations for optimal pain management after unilateral primary TKA.

DESIGN

A narrative review based on published systematic reviews, using modified PROSPECT methodology.

DATA SOURCES

A literature search was performed in EMBASE, MEDLINE, PubMed and Cochrane Databases, between January 2014 and December 2020, for systematic reviews and meta-analyses evaluating analgesic interventions for pain management in patients undergoing TKA.

ELIGIBILITY CRITERIA

Each randomised controlled trial (RCT) included in the selected systematic reviews was critically evaluated and included only if met the PROSPECT requirements. Included studies were evaluated for clinically relevant differences in pain scores, use of nonopioid analgesics, such as paracetamol and nonsteroidal anti-inflammatory drugs and current clinical relevance.

RESULTS

A total of 151 systematic reviews were analysed, 106 RCTs met PROSPECT criteria. Paracetamol and nonsteroidal anti-inflammatory or cyclo-oxygenase-2-specific inhibitors are recommended. This should be combined with a single shot adductor canal block and peri-articular local infiltration analgesia together with a single intra-operative dose of intravenous dexamethasone. Intrathecal morphine (100 μg) may be considered in hospitalised patients only in rare situations when both adductor canal block and local infiltration analgesia are not possible. Opioids should be reserved as rescue analgesics in the postoperative period. Analgesic interventions that could not be recommended were also identified.

CONCLUSION

The present review identified an optimal analgesic regimen for unilateral primary TKA. Future studies to evaluate enhanced recovery programs and specific challenging patient groups are needed.

Single shot adductor canal block combined with intravenous patient-controlled analgesia can be effective as continuous adductor canal block in reducing opioid consumption and breakthrough pain after total knee arthroplasty

PURPOSE

The aim of this study was to compare the following three analgesic methods after Total knee arthroplasty (TKA): intravenous patient-controlled analgesia (IV-PCA), continuous adductor canal block (C-ACB), and intravenous patient-controlled analgesia combined with single shot adductor canal block (PCA + sACB).

METHODS

Records of 482 patients undergoing primary TKA from September 2019 to September 2020 were analyzed. Patients were divided into three pain control groups: IV-PCA (n = 180), C-ACB (n = 173) and PCA + sACB (n = 129). Single shot adductor canal block was performed 24 h after surgery in the PCA + sACB group. Rescue opioid consumption, breakthrough pain, pain numerical rating scale (NRS), and anti-emetics administration were measured from postoperative day (POD) 1 to POD 5.

RESULTS

Rescue opioid consumption was less in C-ACB or PCA + sACB group than in the IV-PCA group at POD1 (p < 0.001 and p = 0.002, respectively). Patients in C-ACB and PCA + sACB groups had less breakthrough pain (NRS > 5) than the IV-PCA group at POD1 (p = 0.007). On POD2, C-ACB was statistically superior to IV-PCA (p = 0.011) in terms of breakthrough pain. Postoperative pain NRS was lower in the C-ACB and PCA + sACB groups than in the IV-PCA group (p = 0.025 and p = 0.019, respectively). The total number of anti-emetics consumption was lower in C-ACB and PCA + sACB groups than in the IV-PCA group (p = 0.003 and p = 0.002, respectively).

CONCLUSION

PCA + sACB not only reduced patients' need for rescue opioids, but also decreased the number of breakthrough pain and anti-emetics compared to IV-PCA in early postoperative days after TKA. However, C-ACB and PCA + sACB did not differ significantly in analgesic efficacy or opioid-related side effects. PCA + sACB can be as effective as C-ACB for patients undergoing TKA.

LEVEL OF EVIDENCE

Retrospective cohort study, level III.

Surgeon administered direct adductor canal block is as good as ultrasound guided adductor canal block in pain management in knee replacements- A retrospective case-control study

Aim

The aim of this study is to assess the feasibility of the DACB in a clinical setting and compare the efficacy of postoperative pain relief after TKR in the patients administered DACB versus USG guided ACB. Also to see efficacy and safety of USACB in patients operated with medial parapatellar and subvastus approach.

Material and methods

250 consecutive patients operated with TKR between Jan 2019 to March 2022 were included. Group A included patients operated with medial parapatellar approach and received USACB, Group B included patients operated with medial parapatellar approach and received DACB while Group C included patients operated with subvastus approach and received USACB. VAS scores between three groups were compared at 12 and 24 h. All three groups of patients were otherwise treated identically in the hospital.

Results

The mean age and BMI was not statistically significant between the three groups. The mean VAS pain score at rest at 12 h was 3.06 ± 1.49 (Group A) vs 1.58 ± 1.19 (Group B) [p < 0.0001] and 3.06 ± 1.49 (Group A) vs 1.88 ± 1.18 (Group C) [p < 0.0001]; and at 24 h was 1.88 ± 1.31 (Group A) vs 2.39 ± 1.27 (Group B) [p = 0.023] and 1.88 ± 1.31 (Group A) vs 2.19 ± 1.29 (Group C) [p = 0.16]. The mean theatre time was 151.9 ± 11.37 min (Group A) vs 141.02 ± 19.46 min (Group B) (p = 0.0003) and 151.9 ± 11.37 min (Group A) vs 150.4 ± 28.74 min (Group C) (p = 0.72). Hospital stay was 3.82 ± 0.80 (Group A) vs 4.0 ± 1.09 (Group B) [p = 0.30] and 3.82 ± 0.80 (Group A) vs 2.7 ± 0.69 (Group C) [p < 0.0001]. Group B and Group C had one complication each.

Conclusion

USG ACB irrespective of approach used remains the gold standard in providing consistent pain relief and thereby facilitating early discharge. However, increased operating room turnover time and repeated top-ups remain a disadvantage. Both the quantum of pain relief and the potential downsides remained the same irrespective of the surgical approach used and whether or not steroid was added to the cocktail used for infiltration. On the other hand, DACB provides a short lasting (24 h) adequate pain relief after TKR with similar low complication rates. The technique of DACB may have a potential for a wider use especially in centres where outpatient arthroplasties are performed, if newer longer acting anaesthetic/analgesic combinations are devised.

Reducing opioid usage in total knee arthroplasty postoperative pain management: a literature review and future directions

Total knee arthroplasty (TKA) is a common orthopedic surgery performed with a projected 3.5 million procedures to be done by 2030. Current postoperative pain management for TKA is insufficient, as it results in extensive opioid consumption and functional decline postoperatively. This study identifies the best practices for postoperative TKA pain management through a literature review of the last three years. Studies utilizing interventional techniques (local infiltration analgesia, nerve blocks) and pharmacologic options were reviewed on PubMed, Embase, Ovid Medline and Scopus. Primary outcomes analyzed were the effect of different analgesic approaches on pain reduction, opioid use reduction and improvements in functional mobility or quadriceps strength postoperatively. Additionally, this paper explores the use of cooled radiofrequency ablation, a minimally invasive therapy, for preoperative and postoperative TKA pain management.

The analgesic efficacy of anterior femoral cutaneous nerve block in combination with femoral triangle block in total knee arthroplasty: a randomized control trial

Background

Ultrasound-guided femoral triangle block (FTB) can provide motor-sparing anterior knee analgesia. However, it may not completely anesthetize the anterior femoral cutaneous nerve (AFCN). We hypothesized that an AFCN block (AFCNB) in combination with a FTB would decrease pain during movement in the immediate 12-hour postoperative compared with a FTB alone.

Methods

Eighty patients scheduled to undergo total knee arthroplasty (TKA) were randomized to receive either FTB alone (FTB group) or AFCNB with FTB (AFCNB + FTB group) as a part of the multimodal analgesic regimen. The primary outcome was pain during movement 12 hours postoperatively. Secondary outcomes included numeric rating scale (NRS) pain scores, incidence of surgical incision site pain, intravenous morphine consumption, immediate functional performance, patient satisfaction, and length of hospital stay.

Results

The NRS pain scores on movement 12 hours postoperatively were significantly lower in patients of AFCNB + FTB group compared to those in patients of FTB group (mean difference, -2.02 [95% confidence interval: -3.14, -0.89], P < 0.001). Incidence of pain at the site of surgical incision in 24 hours postoperatively and morphine consumption in 48 hours postoperatively were significantly lower (P < 0.001) and quadriceps muscle strength at 0 degree immediately after the surgery was significantly greater in patients of AFCNB + FTB group (P = 0.04).

Conclusions

The addition of ultrasound-guided AFCNB to FTB provided more effective analgesia and decreased opioid requirement compared to FTB alone after TKA and may enhance immediate functional performance on the day of surgery.

Administration with corticosteroid relieving pain following total knee arthroplasty: A meta-analysis

BACKGROUND

This meta-analysis compares the effectiveness of corticosteroid in relieving pain and inflammation in total knee arthroplasty (TKA) patients.

METHOD

Randomized controlled trials in PubMed (1996 to March 2020), Embase (1996 to March 2020), and the Cochrane Library (CENTRAL, March 2020) compared corticosteroid and placebo in pain in TKA patients were identified by a software and manual searching. The risk of bias and clinical relevance of the included studies were assessed. Sensitivity analysis was performed by omitting each study in turn. The major outcomes of the studies were analyzed by the Stata 12.0.

RESULTS

13 randomized controlled trials that involved 193 patients were included in the present meta-analysis. The results of the study revealed a significantly lower visual analog scale (VAS) score of pain at rest in the corticosteroid group (12 hours: weighted mean difference (WMD)=-1.35, P = .005; 24 hours: WMD=-1.11, P = .000; 48 hours: WMD=-0.31, P = .000; 72 hours: WMD = -0.30, P = .000). And Postoperative VAS scores during mobilization at 12 hours and 24  hours were significantly lower at corticosteroid group when compared with control group (12 hours: WMD = -0.81, P = 0.000; 24 hours: WMD = -1.66, P = .018). Meta-analyses show that administration of corticosteroid can reduce the length of hospital stay, incidence nausea and the C-reactive protein level. While no significant difference was observed in the VAS scores during mobilization at 48 hours and 72 hours and total morphine consumption (P > .05).

CONCLUSIONS

Compared to the control group, intraoperative corticosteroid was benefit to the pain management in TKA. However, more high-quality studies are still warranted to further validate our findings, considering there are several limitations in this meta-analysis.

Continuous adductor canal block provides better performance after total knee arthroplasty compared with the single-shot adductor canal block?: An updated meta-analysis of randomized controlled trials

BACKGROUND

Adductor canal block (ACB) has emerged as an attractive alternative for femoral nerve blocks (FNB) as the peripheral nerve block of choice for total knee arthroplasty (TKA), preserving quadriceps motor function while providing analgesia comparable to FNB. However, its optimal application for TKA remains controversial. The objective of this meta-analysis was to compare continuous-injection ACB (CACB) vs single-injection ACB (SACB) for postoperative pain control in patients undergoing TKA.

METHODS

This study attempts to identify the available and relevant randomized controlled trials (RCTs) regarding the analgesic effects of CACB compared to SACB in patients undergoing TKA according to electronic databases, including PubMed, Medline, Web of Science, EMbase, and the Cochrane Library, up to September 2019. Primary outcomes in this regard included the use of a visual analogue scale (VAS) pain score with rest or activity, while secondary outcomes were cumulative opioid consumption, length of hospital stay (LOS), complications of vomiting and nausea, and rescue analgesia. The corresponding data were analyzed using RevMan v5.3.

ETHICAL REVIEW

Because all of the data used in this systematic review and meta-analysis has been published, the ethical approval was not necessary RESULTS:: This research included 9 studies comprised of 739 patients. The analyzed outcomes demonstrated that patients who received CACB had a better at rest-VAS scores at 4 hours (P = .007), 8 hors (P < .0001), 12 hours (P < .0001), 24 hours (P = .02), mobilization-VAS score at 48 hours (P < .0001), and rescue analgesia (P = .03) than those who underwent SACB. Nevertheless, no significant differences were present between the 2 strategies in terms of pain VAS scores 48 hours at rest (P = .23) and 24 hours at mobilization (P = .10), complications of vomiting and nausea (P = .42), and length of hospital stay (P = .09).

CONCLUSION

This meta-analysis indicated that CACB is superior to SACB in regard to analgesic effect following TKA. However, due to the variation of the included studies, no firm conclusions can be drawn. Further investigations into RCT are required for verification.

Continuous block at the proximal end of the adductor canal provides better analgesia compared to that at the middle of the canal after total knee arthroplasty: a randomized, double-blind, controlled trial

Background

The optimal position for continuous adductor canal block (ACB) for analgesia after total knee anthroplasty (TKA) remians controversial, mainly due to high variability in the localization of the the adductor canal (AC). Latest neuroanatomy studies show that the nerve to vastus medialis plays an important role in innervating the anteromedial aspect of the knee and dives outside of the exact AC at the proximal end of the AC. Therefore, we hypothesized that continuous ACB at the proximal end of the exact AC could provide a better analgesic effect after TKA compared with that at the middle of the AC (which appeared to only block the saphenous nerve).

Methods

Sixty-two adult patients who were scheduled for a unilateral TKA were randomized to receive continuous ACB at the proximal end or middle of the AC. All patients received patient-controlled intravenous analgesia with sufentanil postoperatively. The primary outcome measure was cumulative sufentanil consumption within 24 h after the surgery, which was analyzed using Mann-Whitney U tests. P-values < 0.05 (two-sided) were considered statistically significant. The secondary outcomes included postoperative sufentanil consumption at other time points, pain at rest and during passive knee flexion, quadriceps motor strength, and other recovery related paramaters.

Results

Sixty patients eventually completed the study (30/group). The 24-h sufentanil consumption was 0.22 μg/kg (interquartile range [IQR]: 0.15–0.40 μg/kg) and 0.39 μg/kg (IQR: 0.23–0.52 μg/kg) in the proximal end and middle groups (P = 0.026), respectively. There were no significant inter-group differences in sufentanil consumption at other time points, pain at rest and during passive knee flexion, quadriceps motor strength, and other recovery related paramaters.

Conclusions

Continuous ACB at the proximal end of the AC has a better opioid-sparing effect without a significant influence on quadriceps motor strength compared to that at the middle of the AC after TKA. These findings indicates that a true ACB may not produce the effective analgesia, instead, the proximal end AC might be a more suitable block to alleviate pain after TKA.

Trial registration

This study was registered at ClinicalTrials.gov (NCT03942133; registration date: May 06, 2019; enrollment date: May 11, 2019).

Proximal versus distal adductor canal blocks for total knee arthroplasty: A protocol for randomized controlled trial

BACKGROUND

Currently, there remains a paucity of literature about the efficiency of proximal adductor canal block (PACB) versus distal adductor canal block (DACB) for pain management after total knee arthroplasty (TKA). The purpose of this study is to perform a randomized controlled trial to compare the efficiency of PACB versus DACB for early postoperative pain treatment after TKA.

METHODS

This study is a 2-arm, parallel-group, randomized controlled trial that is conducted at a single university hospital in China. Subjects presenting for unilateral TKA are randomized in a 1:1 ratio to either a PACB or DACB group. The primary outcome of this noninferiority study is opioid consumption within the first 24 hours following surgery. Secondary outcomes include quadriceps strength, pain scores, distance ambulated, and patient satisfaction. Continuous variables are compared using Student t test.

RESULTS

This clinical trial is expected to provide evidence of whether the PACB and DACB provide similar analgesia after TKA.

TRIAL REGISTRATION

This study protocol was registered in Research Registry (researchregistry5440).

Is continuous catheter adductor canal block better than single-shot canal adductor canal block in primary total knee arthroplasty?: A GRADE analysis of the evidence through a systematic review and meta-analysis

BACKGROUND

The adductor canal block (ACB) has emerged as an alternative to the femoral nerve block (FNB) after total knee arthroplasty. This meta-analysis was conducted to investigate which ACB method provides better pain relief and functional recovery after total knee arthroplasty METHODS:: We conducted a meta-analysis to identify randomized controlled trials involving single-shot adductor canal block (SACB) and continuous catheter ACB (CACB) after TKA up to December 2019 by searching databases including the PubMed, Web of Science, Embase, Cochrane Controlled Trials Register, Cochrane Library, CBM, CNKI, VIP, and Wanfang databases. Finally, we included 8 randomized controlled trials involving 702 knees in our study. We used Review Manager Software and Grading of Recommendations Assessment, Development, and Evaluation profiler to perform the meta-analysis.

RESULTS

Compared with SACB, CACB can achieve better postoperative pain relief at 24 and 48 h both at rest and after mobilization, lower amount of opioid consumption at 72 h, a shorter length of hospital stay (LOH) and larger range of motion (ROM). In addition, the Timed Up and Go (TUG) test results; quadriceps strength; and incidence of complications, including postoperative nausea and vomiting, DVT, catheter-related infections, catheter dislodgement and neurologic deficits, showed no significant difference between the two ACB methods.

CONCLUSION

The results of this study demonstrate that CACB is an effective alternative to SACB and can provide better pain relief, a shorter LOH, more degrees of maximum flexion and a lower amount of opioid consumption over time, but it provides a comparable level of recovery of quadriceps strength and mobility with a similar risk of catheter-related complications. Thus, CACB may be a better analgesia strategy than SACB after TKA at present.