A Randomized Trial of Epidural Analgesia Followed by Continuous Femoral Analgesia Compared with Oral Opioid Analgesia on Short- and Long-Term Functional Recovery After Total Knee Replacement

A pilot study of intraoperative application of cooled radiofrequency to reduce post-operative pain following total knee arthroplasty

BACKGROUND

Total Knee Arthroplasty (TKA) is a successful treatment for end stage knee osteoarthritis (OA), but can be associated with significant pain in the early post-operative period. Cooled radiofrequency ablation (CRFA) has reported to reduce knee OA pain by targeting the periarticular nerves. The objective of this pilot study was to assess the effectiveness of intra-operative CRFA for reducing pain and opiate use after TKA.

METHODS

This was a non randomised prospective study with control group. Participants were sequentially recruited preoperatively and underwent TKA, with CRFA to 6 targeted sites prior to cementing of implants, and were compared to controls who underwent TKA without CRFA. The primary outcome was Day 3 pain scores, and secondary outcomes included week one pain scores, and opiate use up to six weeks post-operative.

RESULTS

17 participants were recruited to the control group and 12 were recruited to the CRFA group. There was no significant difference in demographics or baseline pain scores between the groups. On day 2 the CRFA group had a lower mean pain VAS score of 3.2 compared to 4.4 in the control group (p = 0.03). The mean post operative VAS pain score did not differ between the groups for Day 1, 3, 4, or any other time points up to 6 weeks. There were no significant reduction in opiate use in the CRFA group compared to the control group. There were no adverse events.

CONCLUSION

This study demonstrated intra-operative CRFA was not effective in reducing pain by 50% after TKA in a pilot study.

Functional recovery with peripheral nerve block versus general anesthesia for upper limb surgery: a systematic review

BACKGROUND

Peripheral nerve block is a common anesthetic technique used during orthopedic upper limb surgery. Injection of local anesthetics around the target nerve inhibits the action of voltage-dependent sodium channels, inhibiting neurotransmission of pain impulses and providing motor immobility. Compared to general anesthesia, it could improve functional recovery by inhibiting nociceptive impulses and inflammation, thus reducing postoperative pain and immobilization and improving postoperative rehabilitation. This systematic review evaluates the impact of peripheral nerve block versus general anesthesia on postoperative functional recovery following orthopedic upper limb surgery.

METHODS

We searched CENTRAL, MEDLINE, CINHAL, EMBASE, and Scopus trial databases from inception until September 2021 for studies comparing peripheral nerve block to general anesthesia. We collected data on functional recovery, range of motion, patient satisfaction, quality of life, and return to work. We pooled studies using a random-effects model and summarized the quality of evidence with the GRADE approach.

RESULTS

We assessed 373 citations and 19 full-text articles for eligibility, and included six studies. Six studies reported on functional recovery, but failed to detect a significant superiority of peripheral nerve block over general anesthesia (3 RCT studies, N = 160; SMD -0.15; CI at 95% -0.60-0.3; I² = 45%; p = 0.07; low quality of evidence and 3 observational studies, N = 377; SMD -0.35; CI at 95% -0.71-0.01; I² = 64%; p = 0.06; very low quality of evidence).

CONCLUSIONS

Current literature is limited and fails to identify the benefit of peripheral nerve block on functional recovery. More studies are needed to assess the impact on long-term recovery. Considering the potential impact on clinical practice and training, a prospective study on functional recovery is ongoing (NCT04541745).

TRIAL REGISTRATION

PROSPERO ID CRD42018116298. Registered on December 4, 2018.

The Efficacy and Safety of Regional Nerve Blocks in Total Knee Arthroplasty: Systematic Review and Direct Meta-Analysis

BACKGROUND

Regional nerve blocks are widely used in primary total knee arthroplasty (TKA) to reduce postoperative pain and opioid consumption. The purpose of our study was to evaluate the efficacy and safety of regional nerve blocks after TKA in support of the combined clinical practice guidelines of the American Association of Hip and Knee Surgeons, American Academy of Orthopaedic Surgeons, Hip Society, Knee Society, and American Society of Regional Anesthesia and Pain Management.

METHODS

We searched MEDLINE, Embase, and the Cochrane Central Register of Controlled Trials for studies published before March 24, 2020 on femoral nerve block, adductor canal block, and infiltration between Popliteal Artery and Capsule of Knee in primary TKA. All included studies underwent qualitative and quantitative homogeneity testing followed by a systematic review and direct comparison meta-analysis to assess the efficacy and safety of the regional nerve blocks compared to a control, local peri-articular anesthetic infiltration (PAI), or between regional nerve blocks.

RESULTS

Critical appraisal of 1,673 publications yielded 56 publications representing the best available evidence for analysis. Femoral nerve and adductor canal blocks are effective at reducing postoperative pain and opioid consumption, but femoral nerve blocks are associated with quadriceps weakness. Use of a continuous compared to single shot adductor canal block can improve postoperative analgesia. No difference was noted between an adductor canal block or PAI regarding postoperative pain and opioid consumption, but the combination of both may be more effective.

CONCLUSION

Single shot adductor canal block or PAI should be used to reduce postoperative pain and opioid consumption following TKA. Use of a continuous adductor canal block or a combination of single shot adductor canal block and PAI may improve postoperative analgesia in patients with concern of poor postoperative pain control.

Strategies aimed at preventing long-term opioid use in trauma and orthopaedic surgery: a scoping review

Background

Long-term opioid use, which may have significant individual and societal impacts, has been documented in up to 20% of patients after trauma or orthopaedic surgery. The objectives of this scoping review were to systematically map the research on strategies aiming to prevent chronic opioid use in these populations and to identify knowledge gaps in this area.

Methods

This scoping review is reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR) Checklist. We searched seven databases and websites of relevant organizations. Selected studies and guidelines were published between January 2008 and September 2021. Preventive strategies were categorized as: system-based, pharmacological, educational, multimodal, and others. We summarized findings using measures of central tendency and frequency along with p-values. We also reported the level of evidence and the strength of recommendations presented in clinical guidelines.

Results

A total of 391 studies met the inclusion criteria after initial screening from which 66 studies and 20 guidelines were selected. Studies mainly focused on orthopaedic surgery (62,1%), trauma (30.3%) and spine surgery (7.6%). Among system-based strategies, hospital-based individualized opioid tapering protocols, and regulation initiatives limiting the prescription of opioids were associated with statistically significant decreases in morphine equivalent doses (MEDs) at 1 to 3 months following trauma and orthopaedic surgery. Among pharmacological strategies, only the use of non-steroidal anti-inflammatory drugs and beta blockers led to a significant reduction in MEDs up to 12 months after orthopaedic surgery. Most studies on educational strategies, multimodal strategies and psychological strategies were associated with significant reductions in MEDs beyond 1 month. The majority of recommendations from clinical practice guidelines were of low level of evidence.

Conclusions

This scoping review advances knowledge on existing strategies to prevent long-term opioid use in trauma and orthopaedic surgery patients. We observed that system-based, educational, multimodal and psychological strategies are the most promising. Future research should focus on determining which strategies should be implemented particularly in trauma patients at high risk for long-term use, testing those that can promote a judicious prescription of opioids while preventing an illicit use, and evaluating their effects on relevant patient-reported and social outcomes.

Tranexamic Acid versus Epsilon-Aminocaproic Acid in Total Knee Arthroplasty: A Meta-Analysis

Objective

At present, the effect of tranexamic acid (TXA) and epsilon-aminocaproic acid (EACA) on total knee arthroplasty (TKA) remains controversial. Therefore, the aim of this meta-analysis is to compare the differences between the effects of TXA and EACA in TKA.

Methods

We used electronic databases, including PubMed, Embase, MEDLINE, Ovid, ScienceDirect, Cochran Library, Google Scholar, clinical trial, and Chinese related databases, for literature search to find any effect of TXA and EACA in TKA. The differences between groups were compared by odds ratio (OR), weighted mean difference (WMD), and 95% confidence interval (CI). A total of four studies, including 3 randomized controlled trials (RCT) and 1 cohort study, were involved in this meta-analysis, involving 1836 participants. Among these participants, 816 belonged to the TXA group and 1020 belonged to the EACA group.

Results

Meta-analysis indicated no difference in surgery time (WMD = 0.01, 95% CI -0.35 to 0.36), total amount of blood loss (WMD = 0.14, 95% CI -0.09 to 0.37), transfusion rate (OR = 0.74, 95% CI 0.20 to 2.78), transfusion units per patient (SMD = -0.15, 95% CI -0.54 to 0.25), complications (OR = 0.75, 95% CI 0.37 to 1.55), and length of stay (SMD = -0.01, 95% CI -0.11 to 0.08).

Conclusions

Our results suggest that the effect of TXA is not superior to EACA in TKA. However, this conclusion still needs to be further confirmed by multicenter and large-sample clinical trials.

Peripheral nerve block anesthesia/analgesia for patients undergoing primary hip and knee arthroplasty: recommendations from the International Consensus on Anesthesia-Related Outcomes after Surgery (ICAROS) group based on a systematic review and meta-analysis of current literature

BACKGROUND

Evidence-based international expert consensus regarding the impact of peripheral nerve block (PNB) use in total hip/knee arthroplasty surgery.

METHODS

A systematic review and meta-analysis: randomized controlled and observational studies investigating the impact of PNB utilization on major complications, including mortality, cardiac, pulmonary, gastrointestinal, renal, thromboembolic, neurologic, infectious, and bleeding complications.Medline, PubMed, Embase, and Cochrane Library including Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials, NHS Economic Evaluation Database, were queried from 1946 to August 4, 2020.The Grading of Recommendations Assessment, Development, and Evaluation approach was used to assess evidence quality and for the development of recommendations.

RESULTS

Analysis of 122 studies revealed that PNB use (compared with no use) was associated with lower ORs for (OR with 95% CIs) for numerous complications (total hip and knee arthroplasties (THA/TKA), respectively): cognitive dysfunction (OR 0.30, 95% CI 0.17 to 0.53/OR 0.52, 95% CI 0.34 to 0.80), respiratory failure (OR 0.36, 95% CI 0.17 to 0.74/OR 0.37, 95% CI 0.18 to 0.75), cardiac complications (OR 0.84, 95% CI 0.76 to 0.93/OR 0.83, 95% CI 0.79 to 0.86), surgical site infections (OR 0.55 95% CI 0.47 to 0.64/OR 0.86 95% CI 0.80 to 0.91), thromboembolism (OR 0.74, 95% CI 0.58 to 0.96/OR 0.90, 95% CI 0.84 to 0.96) and blood transfusion (OR 0.84, 95% CI 0.83 to 0.86/OR 0.91, 95% CI 0.90 to 0.92).

CONCLUSIONS

Based on the current body of evidence, the consensus group recommends PNB use in THA/TKA for improved outcomes.

RECOMMENDATION

PNB use is recommended for patients undergoing THA and TKA except when contraindications preclude their use. Furthermore, the alignment of provider skills and practice location resources needs to be ensured. Evidence level: moderate; recommendation: strong.

Assessing outcome in postoperative pain trials: are we missing the point? A systematic review of pain-related outcome domains reported in studies early after total knee arthroplasty

ABSTRACT

The management of acute postoperative pain remains suboptimal. Systematic reviews and Cochrane analysis can assist with collating evidence about treatment efficacy, but the results are limited in part by heterogeneity of endpoints in clinical trials. In addition, the chosen endpoints may not be entirely clinically relevant. To investigate the endpoints assessed in perioperative pain trials, we performed a systematic literature review on outcome domains assessing effectiveness of acute pain interventions in trials after total knee arthroplasty. We followed the Cochrane recommendations for systematic reviews, searching PubMed, Cochrane, and Embase, resulting in the screening of 1590 potentially eligible studies. After final inclusion of 295 studies, we identified 11 outcome domains and 45 subdomains/descriptors with the domain "pain"/"pain intensity" most commonly assessed (98.3%), followed by "analgesic consumption" (88.8%) and "side effects" (75.3%). By contrast, "physical function" (53.5%), "satisfaction" (28.8%), and "psychological function" (11.9%) were given much less consideration. The combinations of outcome domains were inhomogeneous throughout the studies, regardless of the type of pain management investigated. In conclusion, we found that there was high variability in outcome domains and inhomogeneous combinations, as well as inconsistent subdomain descriptions and utilization in trials comparing for effectiveness of pain interventions after total knee arthroplasty. This points towards the need for harmonizing outcome domains, eg, by consenting on a core outcome set of domains which are relevant for both stakeholders and patients. Such a core outcome set should include at least 3 domains from 3 different health core areas such as pain intensity, physical function, and one psychological domain.

Are perioperative interventions effective in preventing chronic pain after primary total knee replacement? A systematic review

OBJECTIVES

For many people with advanced osteoarthritis, total knee replacement (TKR) is an effective treatment for relieving pain and improving function. Features of perioperative care may be associated with the adverse event of chronic pain 6 months or longer after surgery; effects may be direct, for example, through nerve damage or surgical complications, or indirect through adverse events. This systematic review aims to evaluate whether non-surgical perioperative interventions prevent long-term pain after TKR.

METHODS

We conducted a systematic review of perioperative interventions for adults with osteoarthritis receiving primary TKR evaluated in a randomised controlled trial (RCT). We searched The Cochrane Library, MEDLINE, Embase, PsycINFO and CINAHL until February 2018. After screening, two reviewers evaluated articles. Studies at low risk of bias according to the Cochrane tool were included.

INTERVENTIONS

Perioperative non-surgical interventions; control receiving no intervention or alternative treatment.

PRIMARY AND SECONDARY OUTCOME MEASURES

Pain or score with pain component assessed at 6 months or longer postoperative.

RESULTS

44 RCTs at low risk of bias assessed long-term pain. Intervention heterogeneity precluded meta-analysis and definitive statements on effectiveness. Good-quality research provided generally weak evidence for small reductions in long-term pain with local infiltration analgesia (three studies), ketamine infusion (one study), pregabalin (one study) and supported early discharge (one study) compared with no intervention. For electric muscle stimulation (two studies), anabolic steroids (one study) and walking training (one study) there was a suggestion of more clinically important benefit. No concerns relating to long-term adverse events were reported. For a range of treatments there was no evidence linking them with unfavourable pain outcomes.

CONCLUSIONS

To prevent chronic pain after TKR, several perioperative interventions show benefits and merit further research. Good-quality studies assessing long-term pain after perioperative interventions are feasible and necessary to ensure that patients with osteoarthritis achieve good long-term outcomes after TKR.

Peripheral Nerve Blocks and Immediate Postoperative Recovery: A Single-Institution Survey of Perianesthesia Nurses' Preferences and Opinions

PURPOSE

To ascertain the preferences of perianesthesia nurses regarding peripheral nerve blocks (PNBs) and their impact on patient recovery after total joint replacement (TJR).

DESIGN

Survey of perianesthesia nurses at a single medical center.

METHODS

Fifty-nine perianesthesia nurses completed a 23-question survey on PNBs for TJR.

FINDINGS

Most agreed PNBs improved patients' pain after knee, hip, and shoulder TJR (35 [92.1%], 35 [92.1%], and 34 [91.9%], respectively). Most felt lower extremity PNBs increased risk of falling (26 [70.3%]), whereas 7 of 35 (20.0%) felt patients fell more after spinal anesthesia than after general anesthesia. Respondents preferred a block to opioid-based analgesia if they were to have lower extremity TJR or total shoulder replacement (100% [30/30 and 33/33]).

CONCLUSIONS

The perianesthesia nurses surveyed felt PNBs improved pain control and patient recovery despite a perceived risk of falling for lower extremity TJR, and they preferred PNB when considering TJR surgery for themselves.

Radiofrequency ablation of genicular nerves prior to total knee replacement has no effect on postoperative pain outcomes: a prospective randomized sham-controlled trial with 6-month follow-up

BACKGROUND AND OBJECTIVES

Refractory chronic knee pain from osteoarthritis (OA) is commonly treated with total knee arthroplasty (TKA). TKA can be associated with severe postoperative pain and persistent postsurgical knee pain. Poorly controlled postoperative pain can negatively effect functional outcomes following TKA, and effective opioid-sparing analgesia is key to the ideal recovery. Genicular nerve radiofrequency ablation (GN-RFA) has been shown in several trials to be clinically effective in patients with severe refractory knee pain from OA. We aimed to assess if preoperative GN-RFA would improve postoperative pain outcomes following TKA.

METHODS

This was a sham-control prospective clinical trial in which blinded participants were randomized to image-guided GN-RFA or a simulated sham procedure 2-6 weeks prior to elective TKA. Outcomes were assessed at 48 hours and 1, 3 and 6 months following TKA.

RESULTS

Seventy participants enrolled in this study. As compared with sham controls, GN-RFA had no treatment effect on postoperative opioid consumption, pain or functional measures at any time point.

CONCLUSIONS

Cooled RFA of the superior lateral, superior medial and inferomedial genicular nerves, when performed 2-6 weeks prior to elective TKA as part of a multimodal postoperative pain management regime, had no measurable effect on postoperative opioid use, analgesia use or function in the 48 hours following surgery. In addition, we found no longer term effect on outcome measures 1, 3 and 6 months after TKA.

TRIAL REGISTRATION NUMBER

NCT02746874.

A Feasibility Study of Percutaneous Peripheral Nerve Stimulation for the Treatment of Postoperative Pain Following Total Knee Arthroplasty

INTRODUCTION

The objective of the present feasibility study was to investigate the use of a new treatment modality-percutaneous peripheral nerve stimulation (PNS)-in controlling the often severe and long-lasting pain following total knee arthroplasty (TKA).

METHODS

For patients undergoing a primary, unilateral TKA, both femoral and sciatic open-coil percutaneous leads (SPR Therapeutics, Cleveland, OH) were placed up to seven days prior to surgery using ultrasound guidance. The leads were connected to external stimulators and used both at home and in the hospital for up to six weeks total.

RESULTS

In six of seven subjects (86%), the average of daily pain scores across the first two weeks was <4 on the 0-10 Numeric Rating Scale for pain. A majority of subjects (four out of seven; 57%) had ceased opioid use within the first week (median time to opioid cessation for all subjects was six days). Gross sensory/motor function was maintained during stimulation, enabling stimulation during physical therapy and activities of daily living. At 12 weeks following surgery, six of seven subjects had improved by >10% on the Six-Minute Walk Test compared to preoperative levels, and WOMAC scores improved by an average of 85% compared to before surgery. No falls, motor block, or lead infections were reported.

CONCLUSIONS

This feasibility study suggests that for TKA, ultrasound-guided percutaneous PNS is feasible in the immediate perioperative period and may provide analgesia without the undesirable systemic effects of opioids or quadriceps weakness induced by local anesthetics-based peripheral nerve blocks.

Postoperative continuous adductor canal block for total knee arthroplasty improves pain and functional recovery: A randomized controlled clinical trial

STUDY OBJECTIVE

Investigate the use of a postoperative continuous adductor canal block (cACB) after epidural analgesia to decreases opioid consumption and improve visual analog scale (VAS) scores compared to a sham catheter.

DESIGN

Double-blinded randomized placebo-controlled trial.

SETTING

Inpatient setting in tertiary care teaching hospital with outpatient follow-up.

PATIENTS

One-hundred and sixty-five subjects (cACB n = 82 and sham catheter n = 83) with end-stage degenerative joint disease undergoing elective unilateral total knee arthroplasty.

INTERVENTIONS

Patients were block randomized to receive a cACB or sham catheter. An epidural catheter was placed preoperatively and discontinued on postoperative day 1. Patients then received a cACB with bupivacaine or sham catheter which remained for the duration of the hospitalization.

MEASUREMENTS

Primary outcome was total opioid consumption. Secondary outcomes included VAS scores, knee range of motion (ROM), ambulation distance, and WOMAC scores.

MAIN RESULTS

Seventy patients completed the study (cACB n = 38 and sham catheter n = 32). Compared to sham catheter, in the first 20 h after placement of a cACB, patients used 22.5 mg less opioid (95% CI: -43.1 to -1.94 mg, P = 0.03). VAS score area under the curve decreased 7.8 mm (95% CI: -15.5 - -0.058 mm, P = 0.04) with a cACB. At 3-week follow-up, WOMAC scores were significantly improved with the cACB with a mean difference of 8.72 (95% CI: -17.3 to -0.11, P = 0.04). There were no statistically significant differences in secondary outcomes on postoperative day 2. Paired outcomes at 6 weeks compared to baseline ROM, showed significant improvement in knee ROM with a cACB (mean difference 11.77°, 95% CI: 3.1-20.5°, P = 0.01).

CONCLUSION

A postoperative cACB after total knee arthroplasty significantly reduces total opioid consumption and pain scores compared to sham catheter. Ambulatory ability was not affected and patients recovered function earlier. ClinicalTrials.govNCT02121392.

Peripheral nerve blocks and postoperative physical therapy: a single-institution survey of physical therapists' preferences and opinions

BACKGROUND AND AIMS

Our aim was to ascertain the opinions and preferences of physical therapists with regard to use of peripheral nerve blocks and their impact on the recovery of patients undergoing total joint replacement.

METHODS

We conducted an anonymous 24-question survey of 20 full-time inpatient physical therapists at a single tertiary care medical center.

RESULTS

One respondent indicated they never work with patients who have undergone total joint replacement surgery. Nineteen questionnaires were included in the final analysis. Questions omitted by respondents or with write-in answers were not included in the analysis. A majority of respondents (15 [78.9%]) agreed nerve blocks somewhat to greatly improve a patient's pain after total joint replacement surgery. Most respondents answered that nerve blocks somewhat to greatly impede a patient's ability to participate in physical therapy (14 [73.6%]) and make therapy somewhat to very difficult for them as physical therapists (16 [84.2%]). When asked about specific surgeries, (17/18 [94.4%]) and (14/18 [77.8%]) of respondents would prefer that their patients receive periarticular infiltration or no block at all after total knee arthroplasty or total hip arthroplasty, respectively. All respondents (19 [100%]) answered that they thought lower extremity nerve blocks increased a patient's risk of falling after surgery.

CONCLUSIONS

According to the physical therapists we surveyed, nerve blocks impede patient recovery and increase the risk of falls, despite their positive impact on pain control. When considering surgery for themselves, therapists indicated they would not want a nerve block.

Regional anesthesia for pediatric knee surgery: a review of the indications, procedures, outcomes, safety, and challenges

The indications for surgery on the knee in children and adolescents share some similarity to adult practice in that there are an increasing number of sports-related injuries requiring surgical repair. In addition, there are some unique age-related conditions or congenital abnormalities that may present as indications for orthopedic intervention at the level of the knee. The efficacy and safety of peripheral nerve blocks (PNBs) for postoperative analgesia following orthopedic surgery has been well established in adults. Recent studies have also demonstrated earlier functional recovery after surgery in patients who received PNBs. In children, PNB is gaining popularity, and increasing data are emerging to demonstrate the feasibility, efficacy, and safety in this population. In this paper, we will review some of the most common indications for surgery involving the knee in children and the anatomy of knee, associated dermatomal and osteotomal innervation, and the PNBs most commonly used to produce analgesia at the level of the knee. We will review the evidence in support of regional anesthesia in children in terms of both the quality conferred to the immediate postoperative care and the role of continuous PNBs in maintaining effective analgesia following discharge. Also we will discuss some of the subtle challenges in utilizing regional anesthesia in the pediatric patient including the use of general anesthesia when performing regional anesthesia and the issue of monitoring for compartment syndrome. Finally, we will offer some thoughts about areas of practice that are in need of further investigation.

Regional analgesia for improvement of long-term functional outcome after elective large joint replacement

BACKGROUND

Regional analgesia is more effective than conventional analgesia for controlling pain and may facilitate rehabilitation after large joint replacement in the short term. It remains unclear if regional anaesthesia improves functional outcomes after joint replacement beyond three months after surgery.

OBJECTIVES

To assess the effects of regional anaesthesia and analgesia on long-term functional outcomes 3, 6 and 12 months after elective major joint (knee, shoulder and hip) replacement surgery.

SEARCH METHODS

We performed an electronic search of several databases (CENTRAL, MEDLINE, EMBASE, CINAHL), and handsearched reference lists and conference abstracts. We updated our search in June 2015.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) comparing regional analgesia versus conventional analgesia in patients undergoing total shoulder, hip or knee replacement. We included studies that reported a functional outcome with a follow-up of at least three months after surgery.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. We contacted study authors for additional information.

MAIN RESULTS

We included six studies with 350 participants followed for at least three months. All of these studies enrolled participants undergoing total knee replacement. Studies were at least partially blinded. Three studies had a high risk of performance bias and one a high risk of attrition bias, but the risk of bias was otherwise unclear or low.Only one study assessed joint function using a global score. Due to heterogeneity in outcome and reporting, we could only pool three out of six RCTs, with range of motion assessed at three months after surgery used as a surrogate for joint function. All studies had a high risk of detection bias. Using the random-effects model, there was no statistically significant difference between the experimental and control groups (mean difference 3.99 degrees, 95% confidence interval (CI) - 2.23 to 10.21; P value = 0.21, 3 studies, 140 participants, very low quality evidence).We did not perform further analyses because immediate adverse effects were not part of the explicit outcomes of any of these typically small studies, and long-term adverse events after regional anaesthesia are rare.None of the included studies elicited or reported long-term adverse effects like persistent nerve damage.

AUTHORS' CONCLUSIONS

More high-quality studies are needed to establish the effects of regional analgesia on function after major joint replacement, as well as on the risk of adverse events (falls).

Femoral nerve blocks for acute postoperative pain after knee replacement surgery

BACKGROUND

Total knee replacement (TKR) is a common and often painful operation. Femoral nerve block (FNB) is frequently used for postoperative analgesia.

OBJECTIVES

To evaluate the benefits and risks of FNB used as a postoperative analgesic technique relative to other analgesic techniques among adults undergoing TKR.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) 2013, Issue 1, MEDLINE, EMBASE, CINAHL, Web of Science, dissertation abstracts and reference lists of included studies. The date of the last search was 31 January 2013.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) comparing FNB with no FNB (intravenous patient-controlled analgesia (PCA) opioid, epidural analgesia, local infiltration analgesia, and oral analgesia) in adults after TKR. We also included RCTs that compared continuous versus single-shot FNB.

DATA COLLECTION AND ANALYSIS

Two review authors independently performed study selection and data extraction. We undertook meta-analysis (random-effects model) and used relative risk ratios (RRs) for dichotomous outcomes and mean differences (MDs) or standardized mean differences (SMDs) for continuous outcomes. We interpreted SMDs according to rule of thumb where 0.2 or smaller represents a small effect, 0.5 a moderate effect and 0.8 or larger, a large effect.

MAIN RESULTS

We included 45 eligible RCTs (2710 participants) from 47 publications; 20 RCTs had more than two allocation groups. A total of 29 RCTs compared FNB (with or without concurrent treatments including PCA opioid) versus PCA opioid, 10 RCTs compared FNB versus epidural, five RCTs compared FNB versus local infiltration analgesia, one RCT compared FNB versus oral analgesia and four RCTs compared continuous versus single-shot FNB. Most included RCTs were rated as low or unclear risk of bias for the aspects rated in the risk of bias assessment tool, except for the aspect of blinding. We rated 14 (31%) RCTs at high risk for both participant and assessor blinding and rated eight (18%) RCTs at high risk for one blinding aspect.Pain at rest and pain on movement were less for FNB (of any type) with or without a concurrent PCA opioid compared with PCA opioid alone during the first 72 hours post operation. Pooled results demonstrated a moderate effect of FNB for pain at rest at 24 hours (19 RCTs, 1066 participants, SMD -0.72, 95% CI -0.93 to -0.51, moderate-quality evidence) and a moderate to large effect for pain on movement at 24 hours (17 RCTs, 1017 participants, SMD -0.94, 95% CI -1.32 to -0.55, moderate-quality evidence). Pain was also less in each FNB subgroup: single-shot FNB, continuous FNB and continuous FNB + sciatic block, compared with PCA. FNB also was associated with lower opioid consumption (IV morphine equivalent) at 24 hours (20 RCTs, 1156 participants, MD -14.74 mg, 95% CI -18.68 to -10.81 mg, high-quality evidence) and at 48 hours (MD -14.53 mg, 95% CI -20.03 to -9.02 mg), lower risk of nausea and/or vomiting (RR 0.47, 95% CI 0.33 to 0.68, number needed to treat for an additional harmful outcome (NNTH) four, high-quality evidence), greater knee flexion (11 RCTs, 596 participants, MD 6.48 degrees, 95% CI 4.27 to 8.69 degrees, moderate-quality evidence) and greater patient satisfaction (four RCTs, 180 participants, SMD 1.06, 95% CI 0.74 to 1.38, low-quality evidence) compared with PCA.We could not demonstrate a difference in pain between FNB (any type) and epidural analgesia in the first 72 hours post operation, including pain at 24 hours at rest (six RCTs, 328 participants, SMD -0.05, 95% CI -0.43 to 0.32, moderate-quality evidence) and on movement (six RCTs, 317 participants, SMD 0.01, 95% CI -0.21 to 0.24, high-quality evidence). No difference was noted at 24 hours for opioid consumption (five RCTs, 341 participants, MD -4.35 mg, 95% CI -9.95 to 1.26 mg, high-quality evidence) or knee flexion (six RCTs, 328 participants, MD -1.65, 95% CI -5.14 to 1.84, high-quality evidence). However, FNB demonstrated lower risk of nausea/vomiting (four RCTs, 183 participants, RR 0.63, 95% CI 0.41 to 0.97, NNTH 8, moderate-quality evidence) and higher patient satisfaction (two RCTs, 120 participants, SMD 0.60, 95% CI 0.23 to 0.97, low-quality evidence), compared with epidural analgesia.Pooled results of four studies (216 participants) comparing FNB with local infiltration analgesia detected no difference in analgesic effects between the groups at 24 hours for pain at rest (SMD 0.06, 95% CI -0.61 to 0.72, moderate-quality evidence) or pain on movement (SMD 0.38, 95% CI -0.10 to 0.86, low-quality evidence). Only one included RCT compared FNB with oral analgesia. We considered this evidence insufficient to allow judgement of the effects of FNB compared with oral analgesia.Continuous FNB provided less pain compared with single-shot FNB (four RCTs, 272 participants) at 24 hours at rest (SMD -0.62, 95% CI -1.17 to -0.07, moderate-quality evidence) and on movement (SMD -0.42, 95% CI -0.67 to -0.17, high-quality evidence). Continuous FNB also demonstrated lower opioid consumption compared with single-shot FNB at 24 hours (three RCTs, 236 participants, MD -13.81 mg, 95% CI -23.27 to -4.35 mg, moderate-quality evidence).Generally, the meta-analyses demonstrated considerable statistical heterogeneity, with type of FNB, allocation concealment and blinding of participants, personnel and outcome assessors reducing heterogeneity in the analyses. Available evidence was insufficient to allow determination of the comparative safety of the various analgesic techniques. Few RCTs reported on serious adverse effects such as neurological injury, postoperative falls or thrombotic events.

AUTHORS' CONCLUSIONS

Following TKR, FNB (with or without concurrent treatments including PCA opioid) provided more effective analgesia than PCA opioid alone, similar analgesia to epidural analgesia and less nausea/vomiting compared with PCA alone or epidural analgesia. The review also found that continuous FNB provided better analgesia compared with single-shot FNB. RCTs were insufficient to allow definitive conclusions on the comparison between FNB and local infiltration analgesia or oral analgesia.

Continuous femoral nerve block using 0.125% bupivacaine does not prevent early ambulation after total knee arthroplasty

BACKGROUND

Continuous femoral nerve block has been shown to decrease opioid use, improve postoperative pain scores, and decrease length of stay. However, several studies have raised the concern that continuous femoral nerve block may delay patient ambulation and increase the risk of falls during the postoperative period.

QUESTIONS/PURPOSES

This study sought to determine whether continuous femoral nerve block with a single-shot sciatic block prevented early ambulation after total knee arthroplasty (TKA) and whether the technique was associated with adverse effects.

METHODS

Between January 2011 and January 2013, 77 consecutive patients undergoing primary TKAs at an orthopaedic specialty hospital received a continuous femoral nerve block for perioperative analgesia. The femoral block was placed preoperatively with an initial bolus and 76 (99%) patients received a single-shot sciatic nerve block performed at the same time. Fifty-eight percent (n = 45) received an initial bolus of 0.125% bupivacaine and 42% (n = 32) received 0.25% bupivacaine. All 77 patients received 0.125% bupivacaine infusion postoperatively with the continuous femoral nerve block. All patients were provided a knee immobilizer that was worn while they were out of bed and was used until 24 hours after removal of the block. All patients also used a front-wheeled walker to assist with ambulation. All 77 patients had complete records for assessing the end points of interest in this retrospective case series, including distance ambulated each day and whether in-hospital complications could be attributed to the patients' nerve blocks.

RESULTS

Thirty-five patients (45%) ambulated for a mean distance of 19 ± 22 feet on the day of surgery. On postoperative Days 1 and 2, all 77 patients successfully ambulated a mean of 160 ± 112 and 205 ± 123 feet, respectively. Forty-eight patients (62%) had documentation of ascending/descending stairs during their hospital stay. No patient fell during the postoperative period, required return to the operating room, or readmission within 90 days of surgery. One patient experienced a transient foot drop related to the sciatic nerve block, which resolved by postoperative Day 1.

CONCLUSIONS

Continuous femoral nerve block with dilute bupivacaine (0.125%) can be successfully used after TKA without preventing early ambulation. By taking active steps to prevent in-hospital falls, including the use of a knee immobilizer for ambulation while the block is in effect, patients can benefit from the analgesia provided by the block and still ambulate early after TKA.

LEVEL OF EVIDENCE

Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Nerve block of the infrapatellar branch of the saphenous nerve in knee arthroscopy: a prospective, double-blinded, randomized, placebo-controlled trial

BACKGROUND

With the rising use of outpatient knee arthroscopy over the past decade, interest in peripheral nerve blocks during arthroscopy has increased. Femoral nerve blocks are effective but are associated with an inherent risk of the patient falling postoperatively because of quadriceps weakness. We studied blocks of the infrapatellar branch of the saphenous nerve, which produce analgesia in the knee that is similar to that resulting from a femoral nerve block but without associated quadriceps weakness.

METHODS

Thirty-four patients were enrolled into each arm of this prospective, randomized, double-blinded trial comparing 10 mL of 0.25% bupivacaine used as a block of the infrapatellar branch of the saphenous nerve with a placebo during simple knee arthroscopy. Immediate outcome measures included Numeric Rating Scale (NRS) pain scores (0 to 10 points), mobility and discharge times, opioid usage, subjective adverse side effects, and forty-eight-hour anesthesia recovery surveys. Short-term measures included one-week and twelve-week Lysholm knee scores.

RESULTS

No adverse effects or increased quadriceps weakness were observed following use of the nerve block. Improvement in early NRS scores and subjective nausea (p = 0.03) were detected. Patients for whom the block was successful also had improved twelve-week Lysholm knee scores (p = 0.04). No differences in opioid usage, mobility time, forty-eight-hour anesthesia recovery scores, or one-week Lysholm knee scores were found.

CONCLUSIONS

No significant adverse effect or disadvantage was identified for blocks of the infrapatellar branch of the saphenous nerve used in simple knee arthroscopy. In addition to decreased early NRS scores and nausea, blocks of the infrapatellar branch of the saphenous nerve demonstrated potential benefit at twelve weeks after simple knee arthroscopy.