Decreased risk of knee buckling with adductor canal block versus femoral nerve block in total knee arthroplasty: a retrospective cohort study

Comparison of the Effects of Adductor Canal and Femoral Nerve Blocks on Postoperative Opioid Consumption and Inflammatory Factor Levels in Elderly Patients After Total Knee Arthroplasty: A Prospective Observational Study

Purpose

Total Knee Arthroplasty (TKA) is a highly invasive procedure causing severe postoperative pain, which hampers early mobility. Effective pain management is crucial for optimal recovery. This study aimed to evaluate how adductor canal block (ACB) and femoral nerve block (FNB) affect opioid use and inflammation factor levels in elderly TKA patients.

Methods

This prospective observational study included 120 patients who received TKA, and divided them into three groups, based on the different nerve block technique: ACB, FNB, and no intervention before general anesthesia (CON). Postoperative opioid consumption, pain assessment, inflammation factor, knee function recovery and other clinical indicators were recorded.

Results

The CON group had significantly higher cumulative sufentanil consumption compared to the ACB and FNB groups at both 12 h and 48h postoperative (P<0.001). Compared with the CON group, the ACB and FNB groups persistently had lower pain scores until 12 h at rest and 24 h during motion after surgery. The ACB group showed significantly lower serum concentrations of C-reactive protein (CRP) and interleukin-6 (IL-6) compared to the CON group at 24 h postoperative (P=0.017, P=0.009), and IL-6 levels remained significantly lower at 72 h postoperative (P=0.005). Both ACB and FNB groups achieved earlier ambulation compared to the CON group (P=0.002). On the first day postoperative, both the ACB and FNB groups showed significantly better knee motion (P<0.001), quadriceps strength (P<0.001), and daily mobilization (P<0.001) compared to the CON group. Additionally, the ACB group exhibited superior quadriceps strength (P<0.001) and daily mobilization (P<0.001) compared to the FNB group.

Conclusion

The ACB and FNB groups exhibited comparable clinical efficacy outcomes in terms of pain scores and opioid consumption. However, the ACB group experienced reduced postoperative inflammation and improved knee recovery, especially in quadriceps strength.

Characterizing patient factors, perioperative interventions, and outcomes associated with inpatients falls after total knee arthroplasty

INTRODUCTION

Mechanical falls represent a potential adverse event after total knee arthroplasty (TKA) and may introduce further injury and delay postoperative recovery. This study aimed to identify patient characteristics associated with inpatient falls, to determine the impact of inpatient falls on surgical outcomes following TKA, and to describe the relationship between tourniquet and/or adductor canal block (ACB) use and fall rates.

METHODS

Patients undergoing primary, elective TKA at a single institution between 2018 and 2022 were retrospectively analyzed. Patients were stratified into groups based on whether they sustained a postoperative inpatient fall or not. Perioperative characteristics, lengths of stay (LOS), rates of 90-day readmissions, and revisions were compared, and fall characteristics were described. Subanalysis was conducted comparing fall incidence based on tourniquet and/or ACB use.

RESULTS

In total 6472 patients were included with 39 (0.6%) sustaining falls. Falls most commonly occurred on postoperative days one (43.6%) and two (30.8%), and were most commonly due to loss of balance (41.9%) or buckling (35.5%). Six (15.4%) fall patients sustained minor injuries, and one (2.6%) sustained major injury (malleolar fracture requiring non-operative orthopaedic management). The LOS (3.0 ± 1.5 vs 2.3 ± 1.5 days, p = 0.002) and all-cause revision rates at latest follow-up (10.3% vs. 2.0%, p = 0.008) were significantly higher in the fall group. Falls were comparable across subgroups based on tourniquet and/or ACB use (p = 0.429).

CONCLUSION

Patients who fell had a longer LOS and higher revision rate postoperatively. Rates of inpatient falls were comparable regardless of tourniquet and/or ACB use. Concern for inpatient falls should not influence surgeons when considering the use of tourniquets and/or ACBs, though well-designed, large-volume, prospective randomized studies are warranted to better understand this relationship.

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

OBJECTIVE

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

MATERIALS AND METHODS

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

RESULTS

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

CONCLUSION

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

Adductor canal block versus femoral nerve block for pain control after total knee arthroplasty: A systematic review and Meta-analysis

BACKGROUND

Femoral nerve block is a widely accepted nerve block method with evident reduction in consumption of opioid painkiller and minimization of the duration of hospital stay but may cause weakness of quadriceps muscle strength. Adductor canal block is another nerve block technique that attracts the attention of scientific community nowadays because of its possible superiority over Femoral nerve block regarding mobility and muscle strength.

METHODS

This is a systematic review and meta-analysis of 33 studies, aiming to compare femoral nerve block with adductor canal block following total knee arthroplasty regarding pain control and mobilization.

RESULTS

Adductor canal block showed better preservation of quadriceps muscle strength (MD = 0.28, 95% CI [0.11, 0.46], P = .002), and better mobilization up to 2 days postoperatively. However, no significant difference was found between the 2 interventions regarding pain control (MD = 0.06, 95% CI [-0.06, 0.17], P = .33) or opioid consumption (SMD = 0.08, 95% CI [-0.06, 0.22], P = .28) up to 2 days postoperatively. The better mobilization results of adductor canal block did not translate into a significant difference in the risk of falls or patients' satisfaction; however, adductor canal block patients had less mean length of hospital stay than the patients with femoral nerve block.

CONCLUSION

Both femoral nerve block and adductor canal block provide similar results regarding pain control and opioid consumption, however adductor canal block provides better preservation of quadriceps strength and mobilization, giving it more advantage over femoral nerve block.

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.

Significantly earlier ambulation and reduced risk of near-falls with continuous infusion nerve blocks: a retrospective pilot study of adductor canal block compared to femoral nerve block in total knee arthroplasty

Background

Near-falls should be detected to prevent falls related to the earlier ambulation after Total knee arthroplasty (TKA). The quadriceps weakness with femoral nerve block (FNB) has led to a focus on adductor canal block (ACB). We purposed to examine the risk of falls and the earlier ambulation in each continuous infusion nerve block.

Methods

Continuous infusion nerve block (FNB or ACB) was performed until postoperative day (POD) 2 or 3. Pain levels and falls/near-falls with knee-buckling were monitored from POD 1 to POD 3. The score on the manual muscle test, MMT (0 to 5, 5 being normal), of the patients who could ambulate on POD 1, was investigated.

Results

A total of 73 TKA cases, 36 FNB and 37 ACB, met the inclusion criteria. No falls were noted. But episodes of near-falls with knee-buckling were witnessed in 14 (39%) cases in the FNB group and in 4 (11%) in the ACB group (p = 0.0068). In the ACB group, 81.1% of patients could ambulate with parallel bars on POD 1, while only 44.4% of FNB patients could do so (p = 0.0019). The quadriceps MMT values in the ACB group was 2.82, significantly higher than 1.97 in the FNB group (p = 0.0035). There were no significant differences in pain as measured with a numerical rating scale (NRS) and rescue analgesia through POD 3.

Conclusion

ACB was associated with significantly less knee-buckling and earlier ambulation post-TKA, with better quadriceps strength. Our study indicated the incidence of falls and near-falls with continuous infusion nerve blocks, and support the use of ACB to reduce the risk of falls after TKA. It is suggested that a certain number of the patients even with continuous ACB infusion should be considered with the effect of motor branch to prevent falls.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12891-022-05735-6.

Pain levels and patient comfort after lower limb arthroplasty comparing i.v. patient-controlled analgesia, continuous peripheral nerve block and neuraxial analgesia: a retrospective cohort analysis of clinical routine data

BACKGROUND

Insufficient pain control after lower limb arthroplasty results in delayed recovery and increased risk for pain chronicization. The ideal kind of analgesia is still discussed controversially. We conducted a retrospective analysis of single-center routine data from a German university hospital, including patients receiving either total hip (THA) or knee arthroplasty (TKA).

METHODS

All patients received general anesthesia. Patients undergoing THA received either continuous epidural ropivacaine infusion (0.133%, Epi) or patient-controlled analgesia (PCA) with the Wurzburg Pain Drip (tramadol, metamizole and droperidol, WPD) or with piritramide (Pir). After TKA, patients received either continuous femoral nerve block (ropivacaine 0.2%, PNB) or Pir.

RESULTS

The analyzed cohort comprised 769 cases. Use of WPD after THA (n = 333) resulted in significantly reduced Numeric Rating Scale (NRS) values at rest, compared to Epi (n = 48) and Pir (n = 72) (.75 [IQR 1.14] vs. 1.17 [1.5], p = .02 vs. 1.47 [1.33], p < .0001) as well as maximum NRS scores (2.4 [1.7] vs. 3.29 [1.94], p < .001 vs. 3.32 [1.76], p < .0001). Positive feedback during follow-up visits was significantly increased in patients with a WPD PCA (p < .0001), while negative feedback (senso-motoric weakness/technical problems/nausea/dizziness/constipation) was particularly increased in Epi patients and lowest in those with WPD (p < .0001). After TKA, Pir (n = 131) resulted in significantly reduced NRS values at rest, compared to PNB (n = 185) (1.4 [1.4] vs. 1.6 [1.68], p = .02). Positive feedback was increased in patients with a Pir PCA in comparison with PNB (p = .04), while negative feedback was increased in PNB patients (p = .04). Overall, WPD presented with the lowest rate of any complications (8.7%), followed by Pir (20.2%), PNB (27.6%) and Epi (31.3%) (p < .001).

CONCLUSIONS

In the assessed population, the use of a WPD PCA after THA offered better pain control and patient comfort in comparison with continuous epidural or piritramide-based analgesia. After TKA, the use of a Pir PCA provided superior analgesia and a lower complication rate compared to continuous PNB.

Comparing Analgesic Efficacy of a Novel Dual Subsartorial Block Using Two Different Volumes in Patients Undergoing Total Knee Arthroplasty: A Prospective, Double-Blind, Monocentric, Randomised Trial

Introduction: Total knee arthroplasty (TKA) is a life-changing joint surgery that improves health-related quality of life and functional status. Patients in need of this surgery mostly belong to the geriatric age group with limited functional reserves and multiple co-morbidities requiring utmost perioperative care with the most suitable analgesic modalities. Regional analgesia (RA) should provide effective analgesia while allowing early mobility, reduced opioid consumption, and early discharge. Dual subsartorial block (DSB) is a novel procedure-specific, motor-sparing, and opioid-sparing RA technique for TKA surgeries. Our study compared the analgesic efficacy of the two different combinations of volumes used in DSB.

Methods: This prospective randomized comparative study included patients between 25-75 years of age of American Society of Anesthesiology (ASA) I-II grades who underwent an elective cemented unilateral total knee replacement performed via medial approaches under neuraxial anesthesia. A total of 104 patients were divided into two equal groups based on the local anesthetic (LA) volumes (Group A 10/20 ml and Group B 20/10 ml) used in the DSB. Postoperative pain scores (using a visual analog scale) and quadriceps strengths (using neurological exam), and opioid consumption were measured at regular intervals till discharge.

Results: Most patients (71.2%) remained pain-free and comfortable until discharge, while 28.8% complained of pain within 12 hours of DSB. Mean quadriceps strength remained almost normal (4-5/5) until the discharge with no incidences of buckling or fall in either group. Over time, the postoperative trend between the groups showed a significant difference for dynamic pain (p = 0.002) and quadriceps strength (p = <0.001). There was an insignificant difference (p = 0.161) between the groups regarding opioid consumption, with the median oral morphine equivalent of zero in both groups. 

Discussion: The effective analgesic coverage of DSB is based on the involvement of all innervations of the procedure-specific pain generators of TKR surgeries. The specific focus on selective sensory innervations and the type/volume of the LA used makes DSB a motor-sparing RA alternative that facilitates early mobility and discharge. It can provide effective postoperative analgesia without compromising the motor strength of the quadriceps muscle when administered in either 10/20 or 20/10 volumes.

A guide to regional analgesia for Total Knee Arthroplasty

Regional analgesia has been introduced successfully into the postoperative pain management after total knee arthroplasty, reducing pain scores, opioid use and adverse effects.

Combination of regional analgesia techniques is associated with better pain management and lower side effects than single regional techniques.

Adductor canal block provides good analgesia and considerably lower detrimental effect in muscular strength than femoral nerve block, enhancing surgical recovery.

Infiltration techniques may have equivalent analgesic effect than epidural analgesia and peripheral nerve blocks, however there should be awareness of dose dependent toxicity.

Novel long-acting local anesthetics role for regional analgesia is still to be determined, and will require larger randomized trials to support its advantage over traditional local anesthetics.

Cite this article: EFORT Open Rev 2021;6:1181-1192. DOI: 10.1302/2058-5241.6.210045

Decreased Opioid Consumption and Length of Stay Using an IPACK and Adductor Canal Nerve Block following Total Knee Arthroplasty

Peripheral nerve blocks such as a femoral + sciatic block have demonstrated significant pain relief following TKA. However, these nerve blocks have residual motor deficits which prevent immediate postoperative ambulation. The purpose of this study was to compare outcomes in patients undergoing primary TKA with femoral and sciatic (Fem + Sci) motor nerve blocks versus an adductor canal and the interspace between the popliteal artery and the capsule of the posterior knee and adductor canal block (IPACK + ACB) sensory nerve blocks. A total of 100 consecutive patients were reviewed, 50 received Fem + Sci nerve blocks and 50 received IPACK + ACB blocks preoperatively. There were no differences in the two groups with respect to surgical technique, implant type, postoperative pain, and physical therapy protocols. Differences in opioid requirements, length of stay (LOS), distance walked, and common knee scoring systems were analyzed. Among them, 62% IPACK + ACB patients were discharged on postoperative day 1 compared with 14% in the Fem + Sci group (p < 0.0001). The IPACK + ACB patients had a shorter LOS (mean 1.48 days vs. 2.02 days, p < 0.001), ambulated further on postoperative day 0 (mean 21.4 feet vs. 5.3 feet, p < 0.001), and required less narcotics the day after surgery (mean, 15.7 vs. 24.0 morphine equivalents p < 0.0001) and at 2 weeks (mean, 6.2 vs. 9.3 morphine equivalents, p = 0.025). The use of this combination IPACK and ACB demonstrated improved early ambulation with a decrease in opioid use and length of stay compared with a femoral and sciatic motor nerve block in patients undergoing primary TKA.

Retrospective Analysis of Pain Relief in Total Knee Replacement Surgeries

Background and Aims

The aim of the study is to measure the postoperative adequacy of pain relief and functional recovery after unilateral primary total knee arthroplasty or total knee replacement (TKR) with a multimodal approach.

Settings and Design

This was a retrospective observational study done in a tertiary care center.

Materials and Methods

Eighty patients aged 18-65 years (yrs) with ASA Physical Status Classes I, II, and III operated for unilateral primary TKR surgery under suitable Anaesthesia and was administered ultrasound-guided adductor canal block + periarticular infiltration (PI) from January 2018 to January 2019 were included. Thereafter, the patients visual analog scale (VAS) scores at rest, 45° knee flexion, and mobilization as well as additional analgesia given were noted after going through the records at following time points: 12 hourly for 24 h and thereafter on postoperative day 1 (POD1) and POD2. Level of block, adverse events, and functional recovery (time up and go [TUG] test, 10 s walk test) on POD1 and POD2 were also noted.

Statistical Analysis and Results

The statistical software namely SPSS 18.0 were used for the analysis of the data. The mean VAS score at 12 h was 4.33 ± 1.3 which worsened at 24 h with steady improvement over the next 2 days. Similarly, the case with a mean VAS score at 45° flexion and on mobilization showed a similar trend. At 12 h postadductor block, besides intravenous (i.v.) paracetamol, 32.6% of patients were given tramadol 50 mg i.v. whereas one patient was given a buprenorphine patch in addition to tramadol. The number of patients requiring additional tramadol and buprenorphine patch steadily increased over the next 2 days. The average time taken for the TUG test at 24 h was 30.98 ± 4.77 s, and the average time taken for the 10 s walk test at 24 h was 6.16 ± 1.10 steps with improvement in performance over the next 2 days.

Conclusion

In our study, our multimodal analgesia model did not provide satisfactory analgesia though mobilization was not hampered.

Is the proximal adductor canal block a better choice than the distal adductor canal block for primary total knee arthroplasty?: A meta-analysis of randomized controlled trials

BACKGROUND

Total knee arthroplasty is accompanied by moderate to severe postoperative pain. Postoperative pain hampers the functional recovery and lowers patient satisfaction with the surgery. Recently, the adductor canal block (ACB) has been widely used in total knee arthroplasty. However, there is no definite answer as to the location of a continuous block within the ACBs.

METHOD

Randomized controlled trials about relevant studies were searched in PubMed (1996 to Oct 2019), Embase (1996 to Oct 2019), and Cochrane Library (CENTRAL, Oct 2019).

RESULTS

Five studies involving 348 patients met the inclusion criteria. Pooled data indicated that the proximal ACB was as effective as the distal ACB in terms of total opioid consumption (P = .54), average visual analog scale (VAS) score (P = .35), worst VAS score (P = .19), block success rate (P = .86), and time of catheter insertion (P = .54).

CONCLUSIONS

Compared with the distal ACB, the proximal ACB showed similar analgesic efficacy for total opioid consumption, average VAS score, worst VAS score, block success rate, and time of catheter insertion. However, because of the limited number of involved studies, more high-quality studies are needed to further identify the optimal location of the ACB.

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.

Post-operative analgesia techniques after total knee arthroplasty: A narrative review

Post-operative knee pain management has become a challenge to provide early relief and pain-free postoperative care to the patient. The major objectives of post-operative analgesic treatment are to reduce opioid requirements, post-operative pain, and adverse events related to opioid intake. This narrative review aimed to document post-operative analgesia techniques after total knee arthroplasty (TKA). The traditional approach involved high-dose opioid-based regimen, though opioid is considered strong analgesic, but are associated with a number of unwanted side effects to seek for alternative techniques. The role of sciatic nerve block in TKA pain is doubtful. Femoral Nerve Block (FNB) is still considered as the gold standard; however, FNB is associated with quadriceps weakness and risk of fall and sciatic block with foot drop. To overcome these drawback more distal nerve block techniques has evolved, namely saphenous nerve block in adductor canal, selective tibial which are claimed to provide comparable analgesia to that of femoral and sciatic nerve block. The combination of pre-emptive and multi-modal analgesia and technically well-delivered regional nerve blocks and postoperative physical therapy are an essential component which not only minimize the side effects of traditional opioid-based analgesia but also speed up functional recovery, increases patient satisfaction, and reduces the overall length of hospitalization and cost.

Benefit of subcutaneous patient controlled analgesia after total knee arthroplasty

Purpose

Subcutaneous patient-controlled analgesia (PCA) has been widely used for orthopedic surgeries including total knee arthroplasty (TKA). This study aims to clarify the usefulness of subcutaneous PCA in the early phase after TKA.

Methods

Our subjects consisted of 88 osteoarthritis knee patients who underwent primary TKA, and were classified into two groups: 42 patients received a subcutaneous PCA (containing fentanyl and droleptan) after operation (PCA group), and 46 patients were managed without a subcutaneous PCA (control group). We compared the incidence of side effects for 3 days postoperatively, measuring the number of times patients used adjuvant analgesia and range of motion on day 7 between the two groups. 34 of 42 patients in the PCA group tolerated PCA use until POD 3 (continuation sub-group), while 8 patients could not continue PCA (interruption sub-group). Demographic data of the two sub-groups were compared.

Results

The mean number of times adjunctive analgesics were used by the PCA group (3.7 ± 2.2) was significantly less than in the control group (5.4 ± 2.8) (p = 0.0049). There were no significant differences in the frequency of side effects between the two groups. There was no significant difference in range of motion between the two groups. Comparing the continuation and interruption sub-groups, patients over 80 years old were at risk to discontinue a subcutaneous PCA (p = 0.0319, odds ratio 5.4).

Conclusion

These findings demonstrate that subcutaneous PCA would be a safe postoperative pain regimen for TKA patients, but the effect was not enough to promote early functional recovery.

Levels of evidence

Therapeutic, Level Ⅱ.

Enhanced preoperative education about continuous femoral nerve block with patient-controlled analgesia improves the analgesic effect for patients undergoing total knee arthroplasty and reduces the workload for ward nurses

Background

Total knee arthroplasty (TKA) is the most common treatment for end-stage knee osteoarthritis and continuous femoral nerve block (CFNB) has become the gold standard for analgesia. But the lack of knowledge about CFNB and patient-controlled analgesia (PCA) often leads to inappropriate dose of medications and increased workload for ward nurses.

Methods

After retrospectively registering to http://www.chictr.org.cn (ChiCTR1800018957), 60 patients undergoing unilateral TKA were randomly divided into groups A and B (n = 30 each). Patients in group B and their families received a nurse-led preoperative visit the day before surgery focusing on PCA educational pamphlets for postoperative pain management. Before returning to the ward, patients and their families in both groups received face-to-face PCA pump operation training. The usual postoperative follow-up was performed by nurse anesthetists for 2 consecutive days. Visual Analogue Scale (VAS) scores at rest and during movement, knowledge of the PCA evaluated by a ten-question questionnaire, knee flexion angles, and the number of PCA-related nurse calls were recorded.

Results

The VAS scores at rest and during movement of the patients in group B were both significantly lower than in group A on postoperative days 1 and 2. The questionnaire scores of the patients in group B were much higher than those in group A on postoperative day 1, but not on day 2. Patients in the 2 groups had similar knee flexion on postoperative days 1 and 2. Patients in group B asked for assistance from the ward nurses with the PCA fewer times than those in group A, and the ward nurses were more satisfied with the analgesic protocol in group B.

Conclusions

Enhanced preoperative education for CFNB with PCA can provide patients with a better grasp of postoperative pain management, improve the postoperative analgesic effect after TKA, and reduce the PCA-related workload for ward nurses.

Trial registration

This study was retrospectively registered to ChiCTR (identifier: ChiCTR1800018957) on October 18, 2018.

Electronic supplementary material

The online version of this article (10.1186/s12871-019-0826-3) contains supplementary material, which is available to authorized users.

Improved pain control with adductor canal block using liposomal bupivacaine after total knee replacement: a retrospective cohort study

Background

Adductor canal blocks (ACBs), typically administered with a local anesthetic such as bupivacaine, help control perioperative pain after total knee arthroplasty. Recently, liposomal bupivacaine (LB) was introduced in an attempt to extend the duration of analgesia, used primarily in periarticular injections (PAIs). The purpose of this study was to compare pain control and early perioperative outcomes with ACB using LB vs standard bupivacaine (SB).

Methods

We retrospectively compared pain control in a group of 75 patients with ACB and PAI with SB to that of a cohort of 75 patients who received ACB and PAI with LB. The primary outcome measure was pain measured using the visual analog score. The secondary outcome measures were morphine equivalents of pain medication (ME), physical therapy distance ambulated, disposition status, and length of stay.

Results

There were no significant differences between the two cohorts for age, gender, body mass index, preoperative diagnosis, or American Society of Anesthesiologists. Visual analog scores were significantly lower in the LB group for postoperative day (POD) 0 (2.1 vs 2.8, P = .046), POD 1 (2.2 vs 3.3, P < .001), and POD 2 (2.1 vs 3.7, P = .001) than those in the SB group. The LB group consumed significantly fewer ME on the POD 0 (18.7 vs 25.2, P = .02) and POD 1 (23.4 vs 37.8, P = .003), as well as overall ME/day (24.6 vs 41.7, P < .001). The LB group walked more on POD 0 (261.6 vs 108.2, P < .001) and POD 1 (761.5 vs 372.0, P < .001).

Conclusions

We report improved outcomes across all measures for the LB group. There were no adverse events. This study supports the use of LB for ACBs in total knee arthroplasty.

An Exact Localization of Adductor Canal and Its Clinical Significance: A Cadaveric Study

Background and Objectives:

Adductor canal block is a regional anesthetic block procedure commonly employed for knee surgeries. This study aims at locating the adductor canal precisely which will be of great use for the surgeons operating on knee.

Materials and Methods:

Forty cadaveric lower limbs fixed with formalin were utilized for the study. The length of the lower limb from anterior superior iliac spine to the base of patella is measured, and the midpoint between the two is marked. Adductor canal is dissected and the distance between proximal foramen and the midpoint of thigh, the length of the adductor canal, and the distance between the distal foramen and the base of the patella are measured.

Results:

The mean value of the adductor canal is about 10.5 cm. The average distance from anterior superior iliac spine to proximal foramen is 25 cm. The average distance from base of patella to distal foramen is 8.5 cm. In 36 (90%) lower limbs, the proximal foramen is 3 cm distal to the midpoint of the thigh.

Interpretation and Conclusion:

This study suggests that a point more than 3 cm below the midpoint of thigh will be the ideal location for the approach of adductor canal block.

Multimodal Clinical Pathway With Adductor Canal Block Decreases Hospital Length of Stay, Improves Pain Control, and Reduces Opioid Consumption in Total Knee Arthroplasty Patients: A Retrospective Review

BACKGROUND

Total knee arthroplasty volume is increasing significantly in the United States. Reducing hospital length of stay may represent the best method for accommodating expanding volume and reducing costs. We hypothesized that tailoring a clinical pathway to facilitate early ambulation would decrease costs and resource utilization.

METHODS

We conducted a sequential before-and-after study of total knee arthroplasty patients after a phased implementation of a clinical pathway that includes multimodal oral analgesic protocols, adductor canal nerve block, and standardized day of surgery ambulation protocols. Primary outcomes measured were hospital length of stay, total opioid consumption, total antiemetic use, and perioperative pain scores.

RESULTS

Two hundred ninety-five patients were divided into 3 sequential cohorts. Cohort 1 received spinal anesthesia, femoral nerve block, and was not placed into postop day 0 ambulation therapy. Cohort 2 received spinal anesthesia, adductor canal block, and postop day 0 ambulation therapy. Cohort 3 received spinal anesthesia, adductor canal block, postop day 0 ambulation therapy, and standardized oral multimodal analgesic protocol. Cohort 3 had significantly reduced hospital length of stay. Cohorts 2 and 3 had significantly less opioid consumption. Cohort 3 had significantly less total ondansetron consumption compared with cohort 1. Cohort 3 had significantly reduced average pain scores compared with cohort 1.

CONCLUSION

The data demonstrate that tailored clinical pathways designed to facilitate early ambulation can reduce hospital length of stay, reduce opioid consumption, reduce antiemetic use, and improve pain control. The results establish that refined clinical pathways can assist in improving care while increasing value to patients, providers, and systems.

A comparative analysis of femoral nerve block with adductor canal block following total knee arthroplasty: A systematic literature review

Background:

Patients undergoing total knee arthroplasty suffer from moderate-to-severe postoperative pain resulting in immobility-related complications and prolonged hospitalization. Femoral nerve block is associated with reduction in the quadriceps strength and increasing incidence of falls. Adductor canal block has been shown to be as effective as femoral nerve block without causing quadriceps weakness.

Objectives:

To compare outcomes of studies comparing adductor canal block and femoral nerve block in patients undergoing primary total knee arthroplasty.

Data Sources:

Original articles, published between July 2013 and April 2017, comparing the above interventions.

Study Eligibility Criteria, Participants, and Interventions:

Comparison of outcome measures of all original articles shortlisted by the PUBMED and Google Scholar databases search using key words, “adductor canal block; femoral nerve block; total knee arthroplasty; total knee replacement.”

Study Appraisal and Synthesis Methods:

The primary outcome measures reviewed were: pain scores; interventional failure; post-operative opioid consumption; patient fall or near fall during postoperative rehabilitation; and length of stay.

Results:

The opioid consumption was found to be comparable with both the interventions on the first and second postoperative day. Patients administered adductor canal block had better quadriceps power, longer ambulation distance, and shorter length of hospital stay.

Limitations:

Of the studies reviewed five were retrospective and thus data quality amongst the studies may have been compromised.

Conclusions and Implications of Key Findings:

Mobilization and ambulation, which are both important for recovery after total knee arthroplasty are both inhibited less by adductor canal block.