Prospective Randomized Trial Comparing Femoral Nerve Block With Intraoperative Local Anesthetic Injection of Liposomal Bupivacaine in Total Knee Arthroplasty

Periarticular infiltration used in total joint replacements: an update and review article

Periarticular infiltration following total knee and hip arthroplasty has been demonstrated to be equivalent to peripheral nerve blocks for postoperative pain management. The ideal cocktail has not been established yet. We have conducted a literature search on PubMed and Embase. Our search criteria included randomized controlled trials (RCTs) and systematic reviews (SRs). We tried to only include the most recent studies to keep the information current. The included research focused at Dexmedetomidine, Liposomal Bupivacaine, Ropivacaine, Epinephrine, Ketorolac, Morphine, Ketamine and Glucocorticosteroids. Each medication's mode of action, duration, ideal dosage, contraindications, side effects and effectiveness have been summarized in the review article. This article will help the clinician to make an informed evidence-based decision about which medications to include in their ideal cocktail.

Review of cooled radiofrequency ablation utilization for the treatment of symptomatic advanced knee arthritis and total knee arthroplasty

Degenerative knee osteoarthritis is a progressive debilitating condition that affects millions of people worldwide. Most patients experience limited range of motion, inflammation, swelling, and pain. Management options can lead to short- and long-term pain relief. Short-term pain relief usually involves conservative medical treatments such as NSAIDs, weight loss, physical therapy, and corticosteroid injections. The ultimate long-term pain relief treatment method involves total knee arthroplasty. The treatment algorithm for knee OA also includes managing pain until a patient is eligible for arthroplasty. Furthermore, about 20% of patients experience chronic pain after TKA without complications such as hardware loosening and infection with limited treatment options. The pathophysiology of this is unknown. Cooled radiofrequency ablation has been demonstrated to be clinically effective by disrupting the integrity of deep sensory nerves and hence interfering with transmission of pain signal. The analgesic effect after c-RFA has been reported up to 24 months. Here, we present an overview of the clinical application of cooled radiofrequency ablation and a summary of its effectiveness in the treatment of pain in the setting of advanced OA and symptomatic TKA.

Management of uncomplicated total knee arthroplasty chronic pain and stiffness utilizing cooled radiofrequency ablation: a single institution pilot study

OBJECTIVE

The objective of this study is to introduce cooled radiofrequency ablation technical feasibility as an alternative percutaneous image-guided treatment of chronic pain and stiffness in the setting of uncomplicated total knee arthroplasty.

MATERIAL AND METHOD

This retrospective pilot study includes a total of 19 consecutive patients experiencing persistent chronic pain after total knee arthroplasty, without underlying hardware complications who had failed conservative care. Patients initially underwent anesthetic blocks of the genicular nerve branches to determine C-RFA candidacy. After adequate response to the anesthetic blocks (> 50% immediate pain relief), patients were subjected to cooled radiofrequency ablations 2-3 weeks later. Treatment response was evaluated utilizing clinically validated questionnaires (KOOS, the Knee Injury and Osteoarthritis Outcome Score) and visual analog scale (VAS) to assess pain severity, stiffness, functional activities of daily living, and use of pain medication. Follow-up outcome scores were collected up to 1 year after C-RFA procedure.

RESULT

A total of 21 knees were treated consecutively between 4/2019 and 1/2020 (mean age 70.5 years; 5 M:14F). The mean total KOOS score improved significantly from baseline at 35.0 ± 14.0 to 64.2 ± 14.7 at a mean of 10.2 months after treatment (p < 0.0001), with significant improvement in mean stiffness score from 44.8 ± 16.7 to 68.8 ± 20 (p < 0.0001). The mean VAS score improved significantly from baseline at 8.30 ± 1.1 to 2.45 ± 1.8 (p < 0.0001). No major complications were encountered. No patients went on to receive re-treatment, surgical revision, or other intervention.

CONCLUSION

Image-guided genicular nerve cooled radiofrequency ablation offers a promising alternative in treating chronic pain/stiffness in the setting of uncomplicated TKA.

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 Efficacy of Liposomal Bupivacaine for Opioid and Pain Reduction: A Systematic Review of Randomized Clinical Trials

Background The opioid crisis has prompted surgeons to search for alternative postoperative methods of analgesia. Liposomal bupivacaine is a long-acting local anesthetic formulation used for pain, potentially reducing opioid use. Evaluation of liposomal bupivacaine as a viable alternative for pain management is needed. The objective was to assess the efficacy of randomized clinical trials (RCTs) of liposomal bupivacaine in postoperative pain management and opioid consumption. Material and Methods The authors extracted RCTs comparing liposomal bupivacaine versus placebo or active comparators for postoperative pain or opioid reduction from PubMED/MEDLINE, Cochrane Library, and ClinicalTrials.gov. Exclusion criteria included nonhuman studies, non-RCTs, pooled studies, and inability to access full text. The following variables were abstracted: surgical specialty, number of subjects, pain and opioid outcomes, and authors' financial conflicts of interest. Results We identified 77 published RCTs, of which 63 studies with a total of 6770 subjects met inclusion criteria. Liposomal bupivacaine did not demonstrate significant pain relief compared to placebo or active agents in 74.58% of RCTs. Of the studies evaluating narcotic use, liposomal bupivacaine did not show a reduction in opioid consumption in 85.71% of RCTs. Liposomal bupivacaine, when compared to standard bupivacaine or another active agent, yielded no reduction in opioid use in 83.33% and 100.00% of studies, respectively. Clinical trials with a financial conflict of interest relating to the manufacturer of liposomal bupivacaine were significantly more likely to show pain relief (OR: 14.31 [95% CI, 2.8, 73.10], P = 0.0001) and decreased opioid consumption (OR: 12.35 [95% CI 1.40, 109.07], P = 0.0237). Of the 265 unpublished RCTs on ClinicalTrials.gov, 47.54% were withdrawn, terminated, suspended, or completed without study results available. Conclusions The efficacy of liposomal bupivacaine for providing superior postoperative pain control relative to placebo or another active agent is not supported by a majority of RCTs. Underreporting of trial results and bias due to underlying financial relationships amongst authors are two major concerns that should be considered when evaluating the available evidence.

Perineural Liposomal Bupivacaine Is Not Superior to Nonliposomal Bupivacaine for Peripheral Nerve Block Analgesia

BACKGROUND

Liposomal bupivacaine is purported to extend analgesia of peripheral nerve blocks when administered perineurally. However, evidence of the clinical effectiveness of perineural liposomal bupivacaine is mixed. This meta-analysis seeks to evaluate the effectiveness of perineural liposomal bupivacaine in improving peripheral nerve block analgesia as compared with nonliposomal local anesthetics.

METHODS

The authors identified randomized trials evaluating the effectiveness of peripheral nerve block analgesic that compared liposomal bupivacaine with nonliposomal local anesthetics. The primary outcome was the difference in area under the receiver operating characteristics curve (AUC) of the pooled 24- to 72-h rest pain severity scores. Secondary outcomes included postoperative analgesic consumption, time to first analgesic request, incidence of opioid-related side effects, patient satisfaction, length of hospital stay, liposomal bupivacaine side effects, and functional recovery. AUC pain scores were interpreted in light of a minimal clinically important difference of 2.0 cm · h.

RESULTS

Nine trials (619 patients) were analyzed. When all trials were pooled, AUC pain scores ± SD at 24 to 72 h were 7.6 ± 4.9 cm · h and 6.6 ± 4.6 cm · h for nonliposomal and liposomal bupivacaine, respectively. As such, perineural liposomal bupivacaine provided a clinically unimportant benefit by improving the AUC (95% CI) of 24- to 72-h pain scores by 1.0 cm · h (0.5 to 1.6; P = 0.003) compared with nonliposomal bupivacaine. Excluding an industry-sponsored trial rendered the difference between the groups nonsignificant (0.7 cm · h [-0.1 to 1.5]; P = 0.100). Secondary outcome analysis did not uncover any additional benefits to liposomal bupivacaine in pain severity at individual timepoints up to 72 h, analgesic consumption, time to first analgesic request, opioid-related side effects, patient satisfaction, length of hospital stay, and functional recovery. No liposomal bupivacaine side effects were reported.

CONCLUSIONS

Perineural liposomal bupivacaine provided a statistically significant but clinically unimportant improvement in the AUC of postoperative pain scores compared with plain local anesthetic. Furthermore, this benefit was rendered nonsignificant after excluding an industry-sponsored trial, and liposomal bupivacaine was found to be not different from plain local anesthetics for postoperative pain and all other analgesic and functional outcomes. High-quality evidence does not support the use of perineural liposomal bupivacaine over nonliposomal bupivacaine for peripheral nerve blocks.

EDITOR’S PERSPECTIVE

Clinical Effectiveness of Liposomal Bupivacaine Administered by Infiltration or Peripheral Nerve Block to Treat Postoperative Pain

The authors provide a comprehensive summary of all randomized, controlled trials (n = 76) involving the clinical administration of liposomal bupivacaine (Exparel; Pacira Pharmaceuticals, USA) to control postoperative pain that are currently published. When infiltrated surgically and compared with unencapsulated bupivacaine or ropivacaine, only 11% of trials (4 of 36) reported a clinically relevant and statistically significant improvement in the primary outcome favoring liposomal bupivacaine. Ninety-two percent of trials (11 of 12) suggested a peripheral nerve block with unencapsulated bupivacaine provides superior analgesia to infiltrated liposomal bupivacaine. Results were mixed for the 16 trials comparing liposomal and unencapsulated bupivacaine, both within peripheral nerve blocks. Overall, of the trials deemed at high risk for bias, 84% (16 of 19) reported statistically significant differences for their primary outcome measure(s) compared with only 14% (4 of 28) of those with a low risk of bias. The preponderance of evidence fails to support the routine use of liposomal bupivacaine over standard local anesthetics.

Liposomal Bupivacaine Is Both Safe and Effective in Controlling Postoperative Pain After Spinal Surgery in Children: A Controlled Cohort Study

STUDY DESIGN

Retrospective comparative cohort study.

OBJECTIVE

To evaluate: (1) pain relief efficacy; (2) opioid consumption; (3) length of stay (LOS); (4) discharge disposition (DD); and (5) safety and adverse effects of liposomal bupivacaine (LB) in pediatric patients who underwent spinal deformity correction.

SUMMARY OF BACKGROUND DATA

LB is a long-acting, locally injectable anesthetic. Previous orthopedic studies investigating its use have been limited to adult patients. The use of LB as part of postoperative pain management in pediatric patients undergoing spine deformity correction surgery is yet to be evaluated.

MATERIALS AND METHODS

A total of 195 patients that received LB as part of their postoperative pain management regimen were compared with 128 patients who received standard pain management without LB. Pain intensity, opioid consumption, LOS, and DD were recorded. Potential LB-related complications were reported as frequencies and statistically compared for superiority. Noninferiority tests were performed using the Farrington-Manning score test. Multivariate tests based on generalized estimating equations were performed to determine the common and average treatment effects. Odds ratios (OR) with 95% confidence intervals (CI) were calculated.

RESULTS

The LB cohort demonstrated lower pain scores [postoperative day 1 (POD 1)-median=2, interquartile range (IQR)=(0-5) vs. 5 (2.5-7); POD 2-3 (0-5) vs. 4 (3-6); P<0.001], lower overall opioid consumption (78.2 vs. 129 morphine milligram equivalents; P=0.0001) and consistently from POD 0 to 3 (mean differences; 7.47, 9.04, 17.2, and 17.3 morphine milligram equivalents, respectively; P<0.01), shorter LOS (median=3 d, IQR=3-4 vs. 4 d, IQR=4-6; P<0.001), and similar to-home DD (98% vs. 97%). Complications were similar among the cohorts in superiority and 10% noninferiority analyses. Patients in the LB cohort had lower odds for complications (odds ratio=0.77; 95% CI, 0.64-0.93; P=0.009 and 0.67; 95% CI, 0.50-0.90; P=0.008).

CONCLUSIONS

This study demonstrated the safety and efficacy of LB when added to the current multimodal postoperative pain management regimens after pediatric spinal surgery.

LEVEL OF EVIDENCE

Level III.

Future in regional anesthesia: new techniques and technological advancements

Regional anesthesia has a very interesting long history, initially preferred over general anesthesia because of safety concerns, then for a period general anesthesia became safer and was preferred. The use of innovative technologies such as ultrasound technology has made the blocks safer and successful by directly visualizing targeted nerves and the location of local anesthetics. With the wide use of ultrasound in the regional anesthesia field success rate of peripheral nerve blocks increased and novel blocks techniques developed. Moreover, new extended-release local anesthetic agents have begun to be promising time-efficient and longer duration of analgesia with a single injection. In this article, we attempt to summarize some of the novel block techniques, pharmacological agents, and new technologies in the field of regional anesthesia.

Postoperative Pain Management in Total Knee Arthroplasty

Total knee arthroplasty (TKA) is one of the most common surgeries performed to relieve joint pain in patients with end‐stage osteoarthritis or rheumatic arthritis of the knee. However, TKA is followed by moderate to severe postoperative pain that affects postoperative rehabilitation, patient satisfaction, and overall outcomes. Historically, opioids have been widely used for perioperative pain management of TKA. However, opioids are associated with undesirable adverse effects, such as nausea, respiratory depression, and retention of urine, which limit their application in daily clinical practice. The aim of this review was to discuss the current postoperative pain management regimens for TKA. Our review of the literature demonstrated that multimodal analgesia is considered the optimal regimen for perioperative pain management of TKA and improves clinical outcomes and patient satisfaction, through a combination of several types of medications and delivery routes, including preemptive analgesia, neuraxial anesthesia, peripheral nerve blockade, patient‐controlled analgesia and local infiltration analgesia, and oral opioid/nonopioid medications. Multimodal analgesia provides superior pain relief, promotes recovery of the knee, and reduces opioid consumption and related adverse effects in patients undergoing TKA.

Advances of Nano-Structured Extended-Release Local Anesthetics

Extended-release local anesthetics (LAs) have drawn increasing attention with their promising role in improving analgesia and reducing adverse events of LAs. Nano-structured carriers such as liposomes and polymersomes optimally meet the demands of/for extended-release, and have been utilized in drug delivery over decades and showed satisfactory results with extended-release. Based on mature technology of liposomes, EXPAREL, the first approved liposomal LA loaded with bupivacaine, has seen its success in an extended-release form. At the same time, polymersomes has advances over liposomes with complementary profiles, which inspires the emergence of hybrid carriers. This article summarized the recent research successes on nano-structured extended-release LAs, of which liposomal and polymeric are mainstream systems. Furthermore, with continual optimization, drug delivery systems carry properties beyond simple transportation, such as specificity and responsiveness. In the near future, we may achieve targeted delivery and controlled-release properties to satisfy various analgesic requirements.

Comprehensive Comparison of Liposomal Bupivacaine with Femoral Nerve Block for Pain Control Following Total Knee Arthroplasty: An Updated Systematic Review and Meta-Analysis

To compare the efficacy of liposomal bupivacaine (LB) and femoral nerve block following total knee arthroplasty, we conducted this systematic review and meta-analysis. 11 trials with 2,908 patients were included in this study. The pooled data demonstrated that total morphine consumption equivalents during the hospital stay was significantly increased in FNB group. In addition, LB has significantly better outcome in view of the postoperative functional recovery, such as the odds of fall, the incidences of straight leg rise (SLR), the number of patients who can walk independently in the day of surgery,the ambulation distance at POD1, the number of patients discharged at POD1. Consistent with the faster functional recovery, liposomal bupivacaine shortens the length of hospital stay. However, there was no significant difference between LB and FNB in terms of Visual Analogue Score (VAS) during the hospital stay. All in all, liposomal bupivacaine has significantly better outcome in view of the postoperative functional recovery and the length of hospital stay compared with femoral nerve block following the total knee arthroplasty.

The Efficacy of Liposomal Bupivacaine Over Traditional Local Anesthetics in Periarticular Infiltration and Regional Anesthesia During Total Knee Arthroplasty: A Systematic Review and Meta-Analysis

BACKGROUND

Since its Food and Drug Administration approval in 2011 as a local anesthetic for postsurgical analgesia, liposomal bupivacaine (LB) has been incorporated into the periarticular injection (PAI) of many knee surgeons. The slow release of this medication from vesicles should significantly extend the duration of its analgesic effect, but current evidence has not clearly demonstrated this benefit.

METHODS

We systematically searched electronic databases including PubMed, MEDLINE, Cochrane Library, EMBASE, ScienceDirect, and Scopus, as well as the Journal of Arthroplasty web page for relevant articles. All calculations were made using Review Manager 5.3.

RESULTS

We identified 42 studies that compared LB to an alternate analgesic modality. Seventeen of these studies were controlled trials that were included in meta-analysis. Significant differences were seen in pain scores with LB over a peripheral nerve block (mean difference = 0.45, P = .02) and LB over a traditional PAI (standard mean difference = -0.08, P = .004).

CONCLUSION

While LB may offer a statistically significant benefit over a traditional PAI, the increase in pain control may not be clinically significant and it does not appear to offer a benefit in reducing opioid consumption. However, there is no standardization among current studies, as they vary greatly in design, infiltration technique, and outcome measurement, which precludes any reliable summarization of their results. Future independent studies using a standardized protocol are needed to provide clear unbiased evidence.