Efficacy of early postoperative ultrasound-guided femoral nerve block (FNB) combined with an infiltration block between the popliteal artery and the capsule of the knee (IPACK) compared to FNB alone for total knee arthroplasty (TKA)

Efficacy of early postoperative ultrasound-guided femoral nerve block (FNB) combined with an infiltration block between the popliteal artery and the capsule of the knee (IPACK) compared to FNB alone for total knee arthroplasty (TKA) | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Efficacy of early postoperative ultrasound-guided femoral nerve block (FNB) combined with an infiltration block between the popliteal artery and the capsule of the knee (IPACK) compared to FNB alone for total knee arthroplasty (TKA) Pheng Ngov, Mengleang Rek, Xingwang Cheng, Nathan Michaela Henry Nio, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6313558/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Background This study aimed to assess the effectiveness of combining FNB with an IPACK, compared with FNB alone, for early postoperative pain management after total knee arthroplasty (TKA). This novel technique may significantly improve posterior knee pain control and potentially lead to earlier and better functional outcomes for patients. Materials and methods This prospective observational study was conducted between September 2023 and June 2024. The initial 40 consecutive patients received FNB+IPACK, and the subsequent 40 received FNB alone. All patients were evaluated with the visual analog scale (VAS) for pain; the Timed Up & Go (TUG) test for walking and balance; the manual muscle testing (MMT) for muscle strength; range of motion (ROM) for joint flexibility; and anesthesia consumption for preoperative and postoperative pain recorded at 8, 24, and 48 hours. This study assessed various analgesic techniques for pain management and functional outcomes. Results The FNB+IPACK group experienced significantly lower postoperative pain levels at 8, 24, and 48 hours compared with the FNB group ( P < 0.001). Resting pain was significant at the first 8 hours. At 24 hours, the walking VAS score was 3[2-3], with a TUG time of 22[21-23] (both P < 0.001). By 48 hours, the walking VAS score decreased to 1[1-1.75], and the TUG time improved to 18[17-19] (both P < 0.001), reflecting continued pain reduction and increased mobility. Conclusions The FNB+IPACK technique was an excellent analgesic strategy for the TKA postoperative period without adverse effects on motor function. Orthopedic Surgery Femoral nerve block (FNB) IPACK block TKA Pain control Regional anesthesia Figures Figure 1 Figure 2 Figure 3 Introduction Total knee arthroplasty (TKA) often results in significant early postoperative pain, hindering mobility, and rehabilitation, leading to chronic pain, and ultimately reducing patient satisfaction [ 1 , 2 ]. Over 60% of patients who underwent TKA reported moderate to severe pain after surgery [ 3 ]. The use of multimodal analgesia has significantly reduced procedure-related morbidity and the length of hospital stay [ 4 ]. Moreover, these pain management techniques have been linked to a reduction in the adverse impacts of intravenous opioid treatment, including nausea, vomiting, hypotension, respiratory depression, and constipation [ 5 ]. To address these challenges, there has been a growing interest in regional anesthesia techniques that deliver effective analgesia while reducing the reliance on systemic opioids. Among these methods, FNB is a widely recognized analgesic technique and serves as the standard peripheral nerve block [ 6 ]. Notably, FNB has become increasingly notable for its capacity to block sensory innervation to the anterior thigh and knee, significantly alleviating postoperative pain [ 7 ]. Motor block hinders quadriceps rehabilitation, impacting FNB and early mobilization. The femoral nerve lies above the iliopsoas, beneath the fascia iliaca, with the femoral artery and vein as landmarks. Perpendicular ultrasound probe adjustment enhances visibility [ 8 ]. A sciatic nerve block can indeed result in unwanted side effects of foot drop, which can impede the timely identification and management of surgical injuries to the common peroneal nerve [ 2 ]. An alternative approach was a selective tibial nerve block administered in the popliteal fossa, which offers pain relief without the risk of foot drop. Nevertheless, this technique may compromise the sensation in the foot's sole, leading to reduced strength in the plantar flexion movement [ 9 , 10 ]. Materials and methods Study design This prospective observational study (ChiCTR2400093922) was approved by the Ethics Committee of The Second Affiliated Hospital of Chongqing Medical University and included 80 TKA patients assigned to ultrasound-guided FNB and FNB + IPACK groups. Data were collected from November 2023 to June 2024 with informed consent from all participants. Sample size The sample size calculation from the previous study for postoperative VAS scores at 8 hours utilized a power of 80% and a significance level (α) of 0.05 [ 11 ]. Consequently, this resulted in a final sample size of 40 for each group according to the following formula: The study enrolled 100 patients, excluding 10 and losing 10 to follow-up, the remaining 80. These were split into FNB (40) and FNB + IPACK (40) groups in Fig. 1 . Data collection Patients provided consent and assessed discomfort during preoperative visits. A blinded third party recorded all data to maintain study integrity. Preoperative data were collected via the Wen Juan Xing (WJX) survey app, with patients scanning a QR code to complete questionnaires. Postoperative, unique QR codes were generated, and the Visual Analog Scale (VAS) with pain-level images for clarity. Additional data came from physical exams by the same physician. Data were collected preoperative and at 24 and 48 hours postoperative. VAS was used to assess pain at rest (8, 24, and 48 hours) and during walking. The VAS scale ranged from 0 (no pain) to 10 (very severe pain) [ 12 , 13 ]. During walking, ambulation was assessed using the Timed Up and Go (TUG) test. Patients rose from a chair, walked 3 meters with a walking aid if needed, and returned to the chair. A time of ≤ 10 seconds indicated normal gait, while ≥ 14 seconds signified a high fall risk [ 14 , 15 ]. The quadriceps muscle strength was assessed in the supine position using manual muscle testing (MMT), graded 0–5. Grade 0: No contraction. Grade 1: Flicker, no movement. Grade 2: Full ROM without gravity. Grade 3: Full ROM against gravity, no resistance. Grade 4: Full ROM against moderate resistance. Grade 5: Full ROM against maximum resistance [ 16 , 17 ]. A goniometer measured active ROM at rest and in motion. Anesthesia pumps were provided in the Post Anesthesia Care Unit (PACU), and total presses were recorded. Inclusion criteria The qualifying criteria for patients with knee osteoarthritis suitable for total knee replacement were as follows: Age > 45 years No allergy or intolerance to a study drug Knee OA ≥ Kellgren-Lawrence grade 2 Pain unrelieved after 6 months of treatment. Exclusion criteria Bone tumors Hematological disorders (hemophilia, leukemia, etc.) Regional anesthesia contraindications Cognitive impairment unable to cooperate Severe conditions posing high surgical risk Statistical analysis This study utilized the Kolmogorov–Smirnov test to assess data distribution. Categorical data were analyzed using the Chi -square, while the Mann–Whitney U test was used to compare continuous variables. Statistical significance was defined at P < 0.05. Analysis was conducted with SPSS version 29.0. Anesthesia Management Preoperative preparation All patients in both groups received a nerve block before receiving general anesthesia (GA) [ 18 ]. Oxygen levels, heart rate, and blood pressure were monitored. Venous access was established to administer intravenous medications and fluids. Midazolam was administered intravenously at a dose of (0.04–0.1 mg/kg) to provide sedation and reduce anxiety. Propofol at a dose of (1–3 mg/kg) was used IV to induce anesthesia, followed by Sufentanil at a dose of (0.3–0.5 µg/kg) for analgesia. Rocuronium at a dose of (0.3 mg/kg) was administered to achieve muscle relaxation and facilitate incubation. A laryngeal mask airway or endotracheal tube was used once the patient was adequately anesthetized. Anesthesia was maintained by continuous pumping of Propofol (10 mg/kg/h) and Remifentanil (0.15–0.2 µg/kg/min), to maintain an appropriate depth of anesthesia [ 19 ]. Technique for ultrasound-guided FNB The patient was supine with the leg supported and prepped. The transducer was placed below the inguinal crease to locate the femoral artery, femoral nerve (FN), fascia iliaca (FI), and fascia lata. The needle was inserted 1 cm laterally, injecting 1–2 ml of 0.25% Ropivacaine after passing FI. FN displacement confirmed separation and resistance-free injection was ensured [ 20 – 22 ] in Fig. 2 . Sensory block effectiveness access in the cold test on the anterior thigh and medial aspect of the lower leg. The motor block was evaluated on the foot from the table by asking the patient to extend the knee [ 20 , 23 ]. Technique for ultrasound-guided IPACK block The IPACK block was performed after FNB to target the articular branches of the tibial, common peroneal, and obturator nerves while preserving the main nerve trunks. With the knee bent at 90° supine, the ultrasound transducer was placed medially (2–3 cm above the patella) to locate the distal femur and popliteal artery. The needle was inserted anteromedially into the space between them, injecting 40 mg/20 ml 0.25% Ropivacaine and 5 mg/ml Dexamethasone. The needle tip stayed within 2 cm of the lateral popliteal artery to prevent complications[ 20 , 24 – 26 ] in Fig. 3 . Sensory block effectiveness access by cold test on the posterior knee joint capsule and posterior knee structures. VAS scores before and after the block were considered essential [ 20 ]. Surgical Procedure Experienced surgeons performed all procedures under general anesthesia using a standard medial parapatellar approach. A vertical incision was made medial to the tibial tuberosity, extending 5–10 cm above the patella. While ligamentous release and bony resection varied, the use of a cruciate-substituting (CS) implant did not alter the standard technique. All cases used a CS implant by Miceoport, and no suction drainage was applied during closure [ 27 ]. Postoperative preparation Following the procedure, the muscle relaxants were antagonized, leading to the removal of the laryngeal mask airway or endotracheal tube. Upon verification of spontaneous breathing and responsiveness to verbal commands, patients were transferred to the PACU, where all patients received patient-controlled intravenous analgesia (PCIA). It used an anesthesia pump: (Sufentanil 100 µg + Flurbiprofen 100 mg + Ondansetron 16 mg) + saline 0.9% for a total volume of 100 ml. The first dosage was 2 ml, and the automatic background dosage was 2 ml/h. The parameter dose was 0.1–0.2 ml/kg/h—the limit dose was approximately 10–14 ml/h. Only the first press was effective if the patients pressed the button twice or more in 10 minutes. Every press was recorded [ 28 ]. Results Table 1 Comparison of patient characteristics between the FNB and IPACK techniques Variables Category FNB n (%) FNB + IPACK n (%) \(\:{\varvec{\chi\:}}^{2}\) /F P value Sample size 40 40 Gender Man 23 (65.7) 12 (34.3) 6.146 a 0.013 a Woman 28 (62.2) 17(37.8) Age 69.03 ± 7.62 70.13 ± 8.32 0.544 0.539 b BMI 25.54 ± 3.68 25.30 ± 2.65 3.919 0.743 b Operation Site Right 21(46.7) 24(53.3) 0.457 a 0.499 a Left 16 (40) 19 (47.5) Admitted day 7.65 ± 2.71 3.40 ± 0.90 26.3 < 0.001 b Notes: Data are presented as the means ± standard deviations, n (%) indicates significance at P < 0.05 a. Chi -square test b. Independent t -test Both groups had 40 patients each, with a significant sex distribution difference: FNB (65.7% men, 34.3% women) vs. FNB + IPACK (37.8% men, 62.2% women), ( t = 6.146, P = 0.013). No significant differences were found in sex, age, BMI, or operation site. However, the FNB + IPACK group had a significantly shorter hospital stay of 3.40 ± 0.90 days compared to FNB alone of 7.65 ± 2.71 days ( t = 41.50, P < 0.001) in Table 1 . Table 2 Evaluation of pain score and functional outcome in the FNB and FNB + IPACK groups Variables FNB FNB + IPACK Z P value Mdn(IQR) Mdn(IQR) Walking Pain (VAS) Preoperative 6(5–7) 6(5–7) -1.07 0.284 PO in 24 h 4(3–5) 3(2–3) -5.05 < 0.001 PO in 48 h 3(2–3) 1(1-1.75) -6.44 < 0.001 Resting Pain (VAS) Preoperative 4(3–5) 4(3–5) -0.1 0.916 PO in 8 h 3(2–3) 2(2–3) -3.04 0.002 PO in 24 h 2(2–2) 1(1–2) -4.69 < 0.001 PO in 48 h 1(1–2) 0(0–1) -5.57 < 0.001 Notes: Data are presented as median values with corresponding interquartile ranges. Significance: P 0.05). Postoperative, the FNB + IPACK group had significantly lower pain at 24 hours (3[ 2 – 3 ] vs. 4[ 3 – 5 ], P < 0.001) and 48 hours (1[1-1.75] vs. 3[ 2 – 3 ], P < 0.001), showing a sustained analgesic effect see Table 2 . Resting pain Preoperative resting pain levels were comparable between the groups, showing no significant difference. Postoperative, the FNB + IPACK group reported significantly less pain at 8 hours (2[ 2 – 3 ] vs. 3[ 2 – 3 ], P = 0.002), 24 hours (1[ 1 – 2 ] vs. 2[ 2 – 2 ], P < 0.001), and 48 hours (0[0–1] vs. 1[ 1 – 2 ], P < 0.001), demonstrating sustained pain relief in Table 2 . Table 3 Comparative analysis of functional outcomes in the FNB and FNB + IPACK group Variables FNB FNB + IPACK Z P value Mdn(IQR) Mdn(IQR) Sample size 40 40 TUG (s) Preoperative 13(11–13) 12(10–12) -1.91 0.055 PO in 24 h 25(22–26) 22(21–23) -5.47 < 0.001 PO in 48 h 21(19–22) 18(17–19) -6.02 < 0.001 Muscle strength Preoperative 4(3–5) 4(3–5) -0.403 0.687 PO in 24 h 2(2–3) 3(2–3) -2.189 0.029 PO in 48 h 2(2–3) 3(2–3) -2.466 0.014 Range of motion (degree) Preoperative 100(95–100) 100(95-103.75) -1.62 0.104 PO in 24 h 90(86.25-90) 90(90–95) -2.23 0.026 PO in 48 h 90(85-93.75) 92.5(90–95) -3.47 0.001 Anesthesia pump PO in 24 h 4.5(3–6) 3(3–5) -3.08 0.002 PO in 48 h 2(2–3) 1(1–2) -3.87 < 0.001 Notes: Data are articulated as median values with corresponding interquartile ranges Significance P < 0.05 PO: Postoperative TUG The study found no significant difference in preoperative TUG times between groups. However, at 24 hours postoperative, the FNB + IPACK group showed significantly faster mobility (22[ 21 – 23 ] vs. 25[ 22 – 26 ], Z = -5.47, P < 0.001). This improvement persisted at 48 hours (18[ 17 – 19 ] vs. 21[ 19 – 22 ], Z = -6.02, P < 0.001), indicating better functional recovery with the combined block in Table 3 . Muscle strength Preoperative muscle strength was not significantly different between the FNB and FNB + IPACK groups, ( P > 0.05). Moreover, At 24 hours postoperative, the FNB + IPACK group had significantly greater muscle strength than the FNB group (2[ 2 – 3 ] vs. 3[ 2 – 3 ], Z = -2.189, P = 0.029). At 48 hours, this difference persisted, with the FNB group showing more pronounced weakness (2[ 2 – 3 ] vs. 3[ 2 – 3 ], Z = -2.46, P = 0.014) in Table 3 . Range of motion Both groups had similar preoperative ROM with no significant difference ( P > 0.05). At 24 hours postoperative, the FNB + IPACK group showed significantly better ROM than the FNB group (90[90–95] vs. 90[86.25-90], P = 0.026). By 48 hours, this difference was more pronounced (92.5[90–95] vs. 90[85-93.75], P = 0.001) in Table 3 . Anesthesia pump Anesthesia consumption was lower in the FNB + IPACK group at 24 hours (3[ 3 – 5 ] vs. 4.5[ 3 – 6 ], Z = -3.08, P = 0.002) and 48 hours (1[ 1 – 2 ] vs. 2[ 2 – 3 ], Z= -3.87, P < 0.001), indicating superior pain control and reduced analgesic need in Table 3 . Discussion Our study revealed that the FNB + IPACK group reduced pain levels both while walking and at rest within the first 8, 24, and 48 hours postoperative and experienced significantly less pain compared to the FNB group alone. A review by M. Biehl et al revealed that the FNB + IPACK group had better results in NRS score, pain at rest and during movement; and ambulation distance on POD 0, POD 1, and POD 2 [ 29 ]. However, A. S. Deis et al found that the FNB + IPACK group had a significantly shorter hospital stay than the FNB group [ 30 ]. Postoperative ROM was a crucial metric for evaluating outcomes and served as an indicator of the associated muscle strength of the knee [ 31 ]. An additional significant finding in Dündar et al was a better ROM in the IPACK block group at early 24 hours postoperative compared to genicular block and the control group [ 32 ]. Nevertheless, FNB could lead to quadriceps muscle weakness, which may increase the risk of falls [ 33 , 34 ]. The IPACK block delivers pain relief without causing a reduction in muscle strength by precisely blocking the sensory endings in the posterior part of the knee while leaving the motor components of the tibial and peroneal nerves unaffected [ 35 ]. Li, D., et al reported better outcomes such as muscle strength and ROM when IPACK was combined with other regional anesthesia techniques [ 11 ]. Under El-Emam et al reported that compared with ACB alone, IPACK + ACB provided greater muscle strength. [ 36 ]. A study by Hsu et al revealed that combining FNB + IPACK block for 30 minutes before anesthesia, reduced opioid usage, facilitating early functional recovery. Moreover, immediate motor block assessment after general anesthesia was not feasible because patients were unconscious [ 18 ]. In this study, FNB + IPACK group demonstrated faster TUG times, better muscle strength, improved ROM, and lower anesthesia pump usage than those who received only FNB. Hussein et al reported that the TUG test was used to assess ambulation early at 12 and 24 hours postoperative which showed FNB group experienced better pain control than the IPACK group [ 37 ]. The TUG test, along with postoperative walking distance, served as a direct indicator of lower limb mobility [ 38 ]. As reported by many studies, FNB affected the quadriceps muscle, which led to the inability to ambulate early postoperative, they found that FNB was associated with a significantly longer TUG than ACB [ 39 ]. Limitation This single-center observational study may have selection bias. It did not assess anesthesia side effects or chronic pain, focusing on short-term outcomes within 48 hours. Future multicenter studies should evaluate long-term function and pain management. Conclusion The early postoperative in TKA for 24 and 48 hours compared with FNB alone, the FNB + IPACK technique is associated with better pain management and improved functional outcomes. This study revealed superior functional outcomes without compromised motor function, including greater muscle strength, range of motion, and shorter hospital stays. It promotes recovery and faster rehabilitation. It also optimizes mobility, which increases patient satisfaction. The overall quality of care has improved, contributing to better clinical practice. Abbreviations FNB: Femoral nerve block TKA: Total knee arthroplasty IPACK: Infiltration between the popliteal artery and the capsule of the knee VAS: Visual Analog Scale TUG: Timed Up and Go MMT: Manual muscle testing ROM: Range of motion WJX: Wen Juan Xing PACU: The Post-anesthesia Care Unit PA: Popliteal artery PV: Popliteal vein NI: Needle injection FN: Femoral nerve FA: Femoral artery FV: Femoral vein FI: Fascia iliaca FL: Fascia lata LA: Local anesthesia PO: Postoperative POD: Postoperative day IQR: Interquartile range Mdn: Median References Joshi, G.P. and B.O. Ogunnaike, Consequences of inadequate postoperative pain relief and chronic persistent postoperative pain. Anesthesiology Clinics of North America, 2005. 23 (1): p. 21-36. Zhang, B., J.K. Oni, and S.C. 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El-Emam, E.-S.M., Ultrasound-guided adductor canal block versus combined adductor canal and infiltration between the popliteal artery and the posterior capsule of the knee block for osteoarthritis knee pain. Anesthesia Essays and Researches, 2020. 14 (1): p. 127-131. Hussein, M.M., et al., Comparison between Ultrasound Guided Femoral Nerve Block versus IPACK Block in Patients Undergoing Total Knee Replacement on Postoperative Ambulation and Pain: A randomised controlled clinical trial. Sri Lankan Journal of Anaesthesiology, 2024. 32 (2). Bohannon, R.W., Reference values for the timed up and go test: a descriptive meta-analysis. Journal of geriatric physical therapy, 2006. 29 (2): p. 64-68. Hegazy, N.A. and S.S. Sultan, Comparison between effects of adductor canal block and femoral nerve block on early postoperative course in total knee arthroplasty: a prospective double-blind, randomized controlled study. Ain-Shams J Anaesthesiol, 2015. 8 (1): p. 124. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-6313558","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":434388648,"identity":"6fb77741-9c4b-41a1-8598-81d3c4e15124","order_by":0,"name":"Pheng Ngov","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Pheng","middleName":"","lastName":"Ngov","suffix":""},{"id":434388649,"identity":"6e064846-dde0-4f99-bb99-19d8db4b23d9","order_by":1,"name":"Mengleang Rek","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Mengleang","middleName":"","lastName":"Rek","suffix":""},{"id":434389785,"identity":"25d460b7-afb4-4740-a87a-f69fb76ea614","order_by":2,"name":"Xingwang Cheng","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Xingwang","middleName":"","lastName":"Cheng","suffix":""},{"id":434389786,"identity":"8e46aa01-271f-4fc5-a1a1-6a4c703daeae","order_by":3,"name":"Nathan Michaela Henry Nio","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Nathan","middleName":"Michaela Henry","lastName":"Nio","suffix":""},{"id":434389787,"identity":"1275b18e-e302-46f9-a4bc-68e44230d9a6","order_by":4,"name":"Ning Hu","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA0klEQVRIiWNgGAWjYBACAzDJA4QMzAeArAOkaGFjS4BqYSZGCwiw8RgQp8VcIvfghzcyNjLm8j3fJD7U3GEwZ+/H7zrLGXnJknN40ngs23i3Sc449ozBsucwAYfdyDFj5uE5zGNwjHebNA/bYaBIMtFaeJ5J//kH1HL/MfFa2KQZ20C2EAqxM2+MwX4xOJZmbNnbB9R7JtkAv5bjOYYf3vbY2BscPvzwxo9vh+UMjh98gN8aEODtAVMsEgygWCUK8PwAU8wfiFM+CkbBKBgFIw0AAIGZRNWF5/TXAAAAAElFTkSuQmCC","orcid":"","institution":"","correspondingAuthor":true,"prefix":"","firstName":"Ning","middleName":"","lastName":"Hu","suffix":""},{"id":434389788,"identity":"75b939d3-687e-4603-bf12-64941bde6e55","order_by":5,"name":"Kailu Liang","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA3UlEQVRIiWNgGAWjYBACPmYwlcDAxsDcwPDBwMaOoBY2hBbGBsYZBWnJhLUwQLUwALUw83w4xNhAUAs787OHXxjS5PkYGNukbQwOMDOwHz66Ab/D2MyNZRhyDNtAWnIM7vAx8KSl3SDgFzNpyX8VjG3yD0FanjEzSPCYEdDC/k1agqHCHmyLhcFhxgbCWnjMJD8w5CSCtTAQqaVMmoEhLRmopdmyxyAtmY2QX/j5j2+T/MGQbDu/gfngjR9/bOz42Q8fw6sFBJh5UOwlpBwEGH8Qo2oUjIJRMApGLgAAqtY6EgG3qr4AAAAASUVORK5CYII=","orcid":"","institution":"","correspondingAuthor":true,"prefix":"","firstName":"Kailu","middleName":"","lastName":"Liang","suffix":""}],"badges":[],"createdAt":"2025-03-26 14:59:20","currentVersionCode":1,"declarations":{"humanSubjects":true,"vertebrateSubjects":false,"conflictsOfInterestStatement":false,"humanSubjectEthicalGuidelines":true,"humanSubjectConsent":true,"humanSubjectClinicalTrial":true,"humanSubjectCaseReport":false,"vertebrateSubjectEthicalGuidelines":false},"doi":"10.21203/rs.3.rs-6313558/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6313558/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":79339877,"identity":"ea26efe8-4112-4440-8dd1-ae80e88e4729","added_by":"auto","created_at":"2025-03-27 08:28:33","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":205357,"visible":true,"origin":"","legend":"\u003cp\u003ePatient enrollment and exclusion flowchart for the study\u003c/p\u003e","description":"","filename":"floatimage1.png","url":"https://assets-eu.researchsquare.com/files/rs-6313558/v1/43923d1c51719a4a5441d108.png"},{"id":79339878,"identity":"af3d6191-39b8-4534-85eb-152249619fe7","added_by":"auto","created_at":"2025-03-27 08:28:33","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":305294,"visible":true,"origin":"","legend":"\u003cp\u003eFNB landmarks and color Doppler confirmation method.\u003c/p\u003e\n\u003cp\u003e(a) Ultrasound-guided FNB. Needle injection site (\u003cem\u003eNIS\u003c/em\u003e), inguinal crease (\u003cem\u003eIC\u003c/em\u003e).\u003c/p\u003e\n\u003cp\u003e(b) Color Doppler as a confirmation method. Needle injection (\u003cem\u003eNI\u003c/em\u003e), fascia iliaca (\u003cem\u003eFI\u003c/em\u003e), local anesthesia (\u003cem\u003eLA\u003c/em\u003e), femoral nerve (\u003cem\u003eFN\u003c/em\u003e), and femoral artery (\u003cem\u003eFA\u003c/em\u003e) as landmarks.\u003c/p\u003e","description":"","filename":"floatimage2.png","url":"https://assets-eu.researchsquare.com/files/rs-6313558/v1/b504d68c3519bcc23b7956f6.png"},{"id":79339882,"identity":"7162244e-8de6-4f45-833d-8123b50d85ae","added_by":"auto","created_at":"2025-03-27 08:28:33","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":259857,"visible":true,"origin":"","legend":"\u003cp\u003eUltrasound-guided IPACK block\u003c/p\u003e\n\u003cp\u003e(a) Needle injection site (\u003cem\u003eNIS\u003c/em\u003e)\u003c/p\u003e\n\u003cp\u003e(b) Needle trajectory between the femur, popliteal artery (\u003cem\u003ePA\u003c/em\u003e), and popliteal vein (\u003cem\u003ePV\u003c/em\u003e).\u003c/p\u003e","description":"","filename":"floatimage3.png","url":"https://assets-eu.researchsquare.com/files/rs-6313558/v1/35ecbb07857049a31e7a65db.png"},{"id":79341724,"identity":"ce62c879-86ba-4357-ad35-54521d7c1d67","added_by":"auto","created_at":"2025-03-27 08:52:34","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1721409,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6313558/v1/6f2beae5-2065-43d4-a5e3-b0d3d86433e1.pdf"}],"financialInterests":"The authors declare no competing interests.","formattedTitle":"\u003cp\u003e\u003cstrong\u003eEfficacy of early postoperative ultrasound-guided femoral nerve block (FNB) combined with an infiltration block between the popliteal artery and the capsule of the knee (IPACK) compared to FNB alone for total knee arthroplasty (TKA)\u003c/strong\u003e\u003c/p\u003e","fulltext":[{"header":"Introduction","content":"\u003cp\u003eTotal knee arthroplasty (TKA) often results in significant early postoperative pain, hindering mobility, and rehabilitation, leading to chronic pain, and ultimately reducing patient satisfaction [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. Over 60% of patients who underwent TKA reported moderate to severe pain after surgery [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. The use of multimodal analgesia has significantly reduced procedure-related morbidity and the length of hospital stay [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. Moreover, these pain management techniques have been linked to a reduction in the adverse impacts of intravenous opioid treatment, including nausea, vomiting, hypotension, respiratory depression, and constipation [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. To address these challenges, there has been a growing interest in regional anesthesia techniques that deliver effective analgesia while reducing the reliance on systemic opioids. Among these methods, FNB is a widely recognized analgesic technique and serves as the standard peripheral nerve block [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]. Notably, FNB has become increasingly notable for its capacity to block sensory innervation to the anterior thigh and knee, significantly alleviating postoperative pain [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. Motor block hinders quadriceps rehabilitation, impacting FNB and early mobilization. The femoral nerve lies above the iliopsoas, beneath the fascia iliaca, with the femoral artery and vein as landmarks. Perpendicular ultrasound probe adjustment enhances visibility [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eA sciatic nerve block can indeed result in unwanted side effects of foot drop, which can impede the timely identification and management of surgical injuries to the common peroneal nerve [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. An alternative approach was a selective tibial nerve block administered in the popliteal fossa, which offers pain relief without the risk of foot drop. Nevertheless, this technique may compromise the sensation in the foot's sole, leading to reduced strength in the plantar flexion movement [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e].\u003c/p\u003e"},{"header":"Materials and methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e\n \u003ch2\u003eStudy design\u003c/h2\u003e\n \u003cp\u003eThis prospective observational study (ChiCTR2400093922) was approved by the Ethics Committee of The Second Affiliated Hospital of Chongqing Medical University and included 80 TKA patients assigned to ultrasound-guided FNB and FNB\u0026thinsp;+\u0026thinsp;IPACK groups. Data were collected from November 2023 to June 2024 with informed consent from all participants.\u003c/p\u003e\n\u003c/div\u003e\n\u003ch3\u003eSample size\u003c/h3\u003e\n\u003cp\u003eThe sample size calculation from the previous study for postoperative VAS scores at 8 hours utilized a power of 80% and a significance level (\u0026alpha;) of 0.05 [\u003cspan class=\"CitationRef\"\u003e11\u003c/span\u003e]. Consequently, this resulted in a final sample size of 40 for each group according to the following formula:\u003c/p\u003e\n\u003cp\u003e\u003cimg src=\"https://myfiles.space/user_files/122228_c8a1650c59388082/122228_custom_files/img1743058740.png\"\u003e\u003cbr\u003e\u003c/p\u003e\n\u003cp\u003eThe study enrolled 100 patients, excluding 10 and losing 10 to follow-up, the remaining 80. These were split into FNB (40) and FNB\u0026thinsp;+\u0026thinsp;IPACK (40) groups in Fig. \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e.\u003c/p\u003e\n\u003ch3\u003eData collection\u003c/h3\u003e\n\u003cp\u003ePatients provided consent and assessed discomfort during preoperative visits. A blinded third party recorded all data to maintain study integrity. Preoperative data were collected via the Wen Juan Xing (WJX) survey app, with patients scanning a QR code to complete questionnaires. Postoperative, unique QR codes were generated, and the Visual Analog Scale (VAS) with pain-level images for clarity. Additional data came from physical exams by the same physician. Data were collected preoperative and at 24 and 48 hours postoperative. VAS was used to assess pain at rest (8, 24, and 48 hours) and during walking. The VAS scale ranged from 0 (no pain) to 10 (very severe pain) [\u003cspan class=\"CitationRef\"\u003e12\u003c/span\u003e, \u003cspan class=\"CitationRef\"\u003e13\u003c/span\u003e]. During walking, ambulation was assessed using the Timed Up and Go (TUG) test. Patients rose from a chair, walked 3 meters with a walking aid if needed, and returned to the chair. A time of \u0026le;\u0026thinsp;10 seconds indicated normal gait, while\u0026thinsp;\u0026ge;\u0026thinsp;14 seconds signified a high fall risk [\u003cspan class=\"CitationRef\"\u003e14\u003c/span\u003e, \u003cspan class=\"CitationRef\"\u003e15\u003c/span\u003e]. The quadriceps muscle strength was assessed in the supine position using manual muscle testing (MMT), graded 0\u0026ndash;5. Grade 0: No contraction. Grade 1: Flicker, no movement. Grade 2: Full ROM without gravity. Grade 3: Full ROM against gravity, no resistance. Grade 4: Full ROM against moderate resistance. Grade 5: Full ROM against maximum resistance [\u003cspan class=\"CitationRef\"\u003e16\u003c/span\u003e, \u003cspan class=\"CitationRef\"\u003e17\u003c/span\u003e]. A goniometer measured active ROM at rest and in motion. Anesthesia pumps were provided in the Post Anesthesia Care Unit (PACU), and total presses were recorded.\u003c/p\u003e\n\u003ch3\u003eInclusion criteria\u003c/h3\u003e\n\u003cdiv class=\"BlockQuote\"\u003e\n \u003cp\u003eThe qualifying criteria for patients with knee osteoarthritis suitable for total knee replacement were as follows:\u003c/p\u003e\n\u003c/div\u003e\n\u003cul\u003e\n \u003cli\u003e\n \u003cp\u003eAge\u0026thinsp;\u0026gt;\u0026thinsp;45 years\u003c/p\u003e\n \u003c/li\u003e\n \u003cli\u003e\n \u003cp\u003eNo allergy or intolerance to a study drug\u003c/p\u003e\n \u003c/li\u003e\n \u003cli\u003e\n \u003cp\u003eKnee OA\u0026thinsp;\u0026ge;\u0026thinsp;Kellgren-Lawrence grade 2\u003c/p\u003e\n \u003c/li\u003e\n \u003cli\u003e\n \u003cp\u003ePain unrelieved after 6 months of treatment.\u003c/p\u003e\n \u003c/li\u003e\n\u003c/ul\u003e\n\u003cp\u003eExclusion criteria\u003c/p\u003e\n\u003cul\u003e\n \u003cli\u003e\n \u003cp\u003eBone tumors\u003c/p\u003e\n \u003c/li\u003e\n \u003cli\u003e\n \u003cp\u003eHematological disorders (hemophilia, leukemia, etc.)\u003c/p\u003e\n \u003c/li\u003e\n \u003cli\u003e\n \u003cp\u003eRegional anesthesia contraindications\u003c/p\u003e\n \u003c/li\u003e\n \u003cli\u003e\n \u003cp\u003eCognitive impairment unable to cooperate\u003c/p\u003e\n \u003c/li\u003e\n \u003cli\u003e\n \u003cp\u003eSevere conditions posing high surgical risk\u003c/p\u003e\n \u003c/li\u003e\n\u003c/ul\u003e\n\u003cp\u003e\u003c/p\u003e\n\u003ch2\u003eStatistical analysis\u003c/h2\u003e\n\u003cp\u003eThis study utilized the \u003cem\u003eKolmogorov\u0026ndash;Smirnov\u003c/em\u003e test to assess data distribution. Categorical data were analyzed using the \u003cem\u003eChi\u003c/em\u003e-square, while the \u003cem\u003eMann\u0026ndash;Whitney U\u003c/em\u003e test was used to compare continuous variables. Statistical significance was defined at \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05. Analysis was conducted with SPSS version 29.0.\u003c/p\u003e\n\u003cp\u003e\u003c/p\u003e\n\u003ch3\u003eAnesthesia Management\u003c/h3\u003e\n\u003cdiv id=\"Sec10\" class=\"Section2\"\u003e\n \u003ch2\u003ePreoperative preparation\u003c/h2\u003e\n \u003cp\u003eAll patients in both groups received a nerve block before receiving general anesthesia (GA) [\u003cspan class=\"CitationRef\"\u003e18\u003c/span\u003e]. Oxygen levels, heart rate, and blood pressure were monitored. Venous access was established to administer intravenous medications and fluids. Midazolam was administered intravenously at a dose of (0.04\u0026ndash;0.1 mg/kg) to provide sedation and reduce anxiety. Propofol at a dose of (1\u0026ndash;3 mg/kg) was used IV to induce anesthesia, followed by Sufentanil at a dose of (0.3\u0026ndash;0.5 \u0026micro;g/kg) for analgesia. Rocuronium at a dose of (0.3 mg/kg) was administered to achieve muscle relaxation and facilitate incubation. A laryngeal mask airway or endotracheal tube was used once the patient was adequately anesthetized. Anesthesia was maintained by continuous pumping of Propofol (10 mg/kg/h) and Remifentanil (0.15\u0026ndash;0.2 \u0026micro;g/kg/min), to maintain an appropriate depth of anesthesia [\u003cspan class=\"CitationRef\"\u003e19\u003c/span\u003e].\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec11\" class=\"Section2\"\u003e\n \u003ch2\u003eTechnique for ultrasound-guided FNB\u003c/h2\u003e\n \u003cp\u003eThe patient was supine with the leg supported and prepped. The transducer was placed below the inguinal crease to locate the femoral artery, femoral nerve (FN), fascia iliaca (FI), and fascia lata. The needle was inserted 1 cm laterally, injecting 1\u0026ndash;2 ml of 0.25% Ropivacaine after passing FI. FN displacement confirmed separation and resistance-free injection was ensured [\u003cspan class=\"CitationRef\"\u003e20\u003c/span\u003e\u0026ndash;\u003cspan class=\"CitationRef\"\u003e22\u003c/span\u003e] in Fig. \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e.\u003c/p\u003e\n \u003cp\u003eSensory block effectiveness access in the cold test on the anterior thigh and medial aspect of the lower leg. The motor block was evaluated on the foot from the table by asking the patient to extend the knee [\u003cspan class=\"CitationRef\"\u003e20\u003c/span\u003e, \u003cspan class=\"CitationRef\"\u003e23\u003c/span\u003e].\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec12\" class=\"Section2\"\u003e\n \u003ch2\u003eTechnique for ultrasound-guided IPACK block\u003c/h2\u003e\n \u003cp\u003eThe IPACK block was performed after FNB to target the articular branches of the tibial, common peroneal, and obturator nerves while preserving the main nerve trunks. With the knee bent at 90\u0026deg; supine, the ultrasound transducer was placed medially (2\u0026ndash;3 cm above the patella) to locate the distal femur and popliteal artery. The needle was inserted anteromedially into the space between them, injecting 40 mg/20 ml 0.25% Ropivacaine and 5 mg/ml Dexamethasone. The needle tip stayed within 2 cm of the lateral popliteal artery to prevent complications[\u003cspan class=\"CitationRef\"\u003e20\u003c/span\u003e, \u003cspan class=\"CitationRef\"\u003e24\u003c/span\u003e\u0026ndash;\u003cspan class=\"CitationRef\"\u003e26\u003c/span\u003e] in Fig. \u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003e.\u003c/p\u003e\n \u003cp\u003eSensory block effectiveness access by cold test on the posterior knee joint capsule and posterior knee structures. VAS scores before and after the block were considered essential [\u003cspan class=\"CitationRef\"\u003e20\u003c/span\u003e].\u003c/p\u003e\n \u003cp\u003e\u003cbr\u003e\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec13\" class=\"Section2\"\u003e\n \u003ch2\u003eSurgical Procedure\u003c/h2\u003e\n \u003cp\u003eExperienced surgeons performed all procedures under general anesthesia using a standard medial parapatellar approach. A vertical incision was made medial to the tibial tuberosity, extending 5\u0026ndash;10 cm above the patella. While ligamentous release and bony resection varied, the use of a cruciate-substituting (CS) implant did not alter the standard technique. All cases used a CS implant by Miceoport, and no suction drainage was applied during closure [\u003cspan class=\"CitationRef\"\u003e27\u003c/span\u003e].\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec14\" class=\"Section2\"\u003e\n \u003ch2\u003ePostoperative preparation\u003c/h2\u003e\n \u003cp\u003eFollowing the procedure, the muscle relaxants were antagonized, leading to the removal of the laryngeal mask airway or endotracheal tube. Upon verification of spontaneous breathing and responsiveness to verbal commands, patients were transferred to the PACU, where all patients received patient-controlled intravenous analgesia (PCIA). It used an anesthesia pump: (Sufentanil 100 \u0026micro;g\u0026thinsp;+\u0026thinsp;Flurbiprofen 100 mg\u0026thinsp;+\u0026thinsp;Ondansetron 16 mg)\u0026thinsp;+\u0026thinsp;saline 0.9% for a total volume of 100 ml. The first dosage was 2 ml, and the automatic background dosage was 2 ml/h. The parameter dose was 0.1\u0026ndash;0.2 ml/kg/h\u0026mdash;the limit dose was approximately 10\u0026ndash;14 ml/h. Only the first press was effective if the patients pressed the button twice or more in 10 minutes. Every press was recorded [\u003cspan class=\"CitationRef\"\u003e28\u003c/span\u003e].\u003c/p\u003e\n\u003c/div\u003e"},{"header":"Results","content":"\u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eComparison of patient characteristics between the FNB and IPACK techniques\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"6\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eVariables\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eCategory\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eFNB\u003c/p\u003e \u003cp\u003en (%)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eFNB\u0026thinsp;+\u0026thinsp;IPACK\u003c/p\u003e \u003cp\u003en (%)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:{\\varvec{\\chi\\:}}^{2}\\)\u003c/span\u003e\u003c/span\u003e/F\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eP value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eSample size\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e40\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e40\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eGender\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003eMan\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e23 (65.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e12 (34.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e6.146\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.013\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003eWoman\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e28 (62.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e17(37.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eAge\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e69.03\u0026thinsp;\u0026plusmn;\u0026thinsp;7.62\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e70.13\u0026thinsp;\u0026plusmn;\u0026thinsp;8.32\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.544\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.539\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eBMI\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e25.54\u0026thinsp;\u0026plusmn;\u0026thinsp;3.68\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e25.30\u0026thinsp;\u0026plusmn;\u0026thinsp;2.65\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e3.919\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.743\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eOperation Site\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003eRight\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e21(46.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e24(53.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.457\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.499\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003eLeft\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e16 (40)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e19 (47.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eAdmitted day\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e7.65\u0026thinsp;\u0026plusmn;\u0026thinsp;2.71\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3.40\u0026thinsp;\u0026plusmn;\u0026thinsp;0.90\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e26.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"6\"\u003eNotes: Data are presented as the means\u0026thinsp;\u0026plusmn;\u0026thinsp;standard deviations, n (%) indicates significance at \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05\u003c/td\u003e\u003c/tr\u003e \u003ctr\u003e\u003ctd colspan=\"6\"\u003ea. \u003cem\u003eChi\u003c/em\u003e-square test\u003c/td\u003e\u003c/tr\u003e \u003ctr\u003e\u003ctd colspan=\"6\"\u003eb. Independent \u003cem\u003et\u003c/em\u003e-test\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eBoth groups had 40 patients each, with a significant sex distribution difference: FNB (65.7% men, 34.3% women) vs. FNB\u0026thinsp;+\u0026thinsp;IPACK (37.8% men, 62.2% women), (\u003cem\u003et\u003c/em\u003e\u0026thinsp;=\u0026thinsp;6.146, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.013). No significant differences were found in sex, age, BMI, or operation site. However, the FNB\u0026thinsp;+\u0026thinsp;IPACK group had a significantly shorter hospital stay of 3.40\u0026thinsp;\u0026plusmn;\u0026thinsp;0.90 days compared to FNB alone of 7.65\u0026thinsp;\u0026plusmn;\u0026thinsp;2.71 days (\u003cem\u003et\u003c/em\u003e\u0026thinsp;=\u0026thinsp;41.50, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.001) in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eEvaluation of pain score and functional outcome in the FNB and FNB\u0026thinsp;+\u0026thinsp;IPACK groups\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"5\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eVariables\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eFNB\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eFNB\u0026thinsp;+\u0026thinsp;IPACK\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eZ\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eP value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMdn(IQR)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eMdn(IQR)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eWalking Pain (VAS)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"4\" nameend=\"c5\" namest=\"c2\"\u003e\u0026nbsp;\u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePreoperative\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e6(5\u0026ndash;7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e6(5\u0026ndash;7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e-1.07\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.284\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePO in 24 h\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e4(3\u0026ndash;5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3(2\u0026ndash;3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e-5.05\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePO in 48 h\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e3(2\u0026ndash;3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1(1-1.75)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e-6.44\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eResting Pain (VAS)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"4\" nameend=\"c5\" namest=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePreoperative\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e4(3\u0026ndash;5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e4(3\u0026ndash;5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e-0.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.916\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePO in 8 h\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e3(2\u0026ndash;3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2(2\u0026ndash;3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e-3.04\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.002\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePO in 24 h\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2(2\u0026ndash;2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1(1\u0026ndash;2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e-4.69\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePO in 48 h\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1(1\u0026ndash;2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0(0\u0026ndash;1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e-5.57\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"5\"\u003eNotes: Data are presented as median values with corresponding interquartile ranges.\u003c/td\u003e\u003c/tr\u003e \u003ctr\u003e\u003ctd colspan=\"5\"\u003eSignificance: \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05\u003c/td\u003e\u003c/tr\u003e \u003ctr\u003e\u003ctd colspan=\"5\"\u003ePO: Postoperative\u003c/td\u003e\u003c/tr\u003e \u003ctr\u003e\u003ctd colspan=\"5\"\u003eIQR: Interquartile range\u003c/td\u003e\u003c/tr\u003e \u003ctr\u003e\u003ctd colspan=\"5\"\u003eMdn: Median\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cdiv id=\"Sec16\" class=\"Section2\"\u003e \u003ch2\u003eWalking pain\u003c/h2\u003e \u003cp\u003eThe results revealed that preoperative walking pain was not significantly different between the two groups (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026gt;\u0026thinsp;0.05). Postoperative, the FNB\u0026thinsp;+\u0026thinsp;IPACK group had significantly lower pain at 24 hours (3[\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e] vs. 4[\u003cspan additionalcitationids=\"CR4\" citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e], \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.001) and 48 hours (1[1-1.75] vs. 3[\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e], \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.001), showing a sustained analgesic effect see Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec17\" class=\"Section2\"\u003e \u003ch2\u003eResting pain\u003c/h2\u003e \u003cp\u003ePreoperative resting pain levels were comparable between the groups, showing no significant difference. Postoperative, the FNB\u0026thinsp;+\u0026thinsp;IPACK group reported significantly less pain at 8 hours (2[\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e] vs. 3[\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e], \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.002), 24 hours (1[\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e] vs. 2[\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e], \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.001), and 48 hours (0[0\u0026ndash;1] vs. 1[\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e], \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.001), demonstrating sustained pain relief in Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eComparative analysis of functional outcomes in the FNB and FNB\u0026thinsp;+\u0026thinsp;IPACK group\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"5\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eVariables\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eFNB\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eFNB\u0026thinsp;+\u0026thinsp;IPACK\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eZ\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eP value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMdn(IQR)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eMdn(IQR)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSample size\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e40\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e40\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" morerows=\"1\" nameend=\"c5\" namest=\"c4\" rowspan=\"2\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eTUG (s)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePreoperative\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e13(11\u0026ndash;13)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e12(10\u0026ndash;12)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e-1.91\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.055\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePO in 24 h\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e25(22\u0026ndash;26)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e22(21\u0026ndash;23)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e-5.47\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePO in 48 h\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e21(19\u0026ndash;22)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e18(17\u0026ndash;19)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e-6.02\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eMuscle strength\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"4\" nameend=\"c5\" namest=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePreoperative\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e4(3\u0026ndash;5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e4(3\u0026ndash;5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e-0.403\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.687\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePO in 24 h\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2(2\u0026ndash;3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3(2\u0026ndash;3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e-2.189\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.029\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePO in 48 h\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2(2\u0026ndash;3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3(2\u0026ndash;3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e-2.466\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.014\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eRange of motion (degree)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"4\" nameend=\"c5\" namest=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePreoperative\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e100(95\u0026ndash;100)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e100(95-103.75)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e-1.62\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.104\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePO in 24 h\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e90(86.25-90)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e90(90\u0026ndash;95)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e-2.23\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.026\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePO in 48 h\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e90(85-93.75)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e92.5(90\u0026ndash;95)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e-3.47\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eAnesthesia pump\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"4\" nameend=\"c5\" namest=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePO in 24 h\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e4.5(3\u0026ndash;6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3(3\u0026ndash;5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e-3.08\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.002\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePO in 48 h\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2(2\u0026ndash;3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1(1\u0026ndash;2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e-3.87\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"5\"\u003eNotes: Data are articulated as median values with corresponding interquartile ranges\u003c/td\u003e\u003c/tr\u003e \u003ctr\u003e\u003ctd colspan=\"5\"\u003eSignificance \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05\u003c/td\u003e\u003c/tr\u003e \u003ctr\u003e\u003ctd colspan=\"5\"\u003ePO: Postoperative\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec18\" class=\"Section2\"\u003e \u003ch2\u003eTUG\u003c/h2\u003e \u003cp\u003eThe study found no significant difference in preoperative TUG times between groups. However, at 24 hours postoperative, the FNB\u0026thinsp;+\u0026thinsp;IPACK group showed significantly faster mobility (22[\u003cspan additionalcitationids=\"CR22\" citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e] vs. 25[\u003cspan additionalcitationids=\"CR23 CR24 CR25\" citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e], Z = -5.47, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.001). This improvement persisted at 48 hours (18[\u003cspan additionalcitationids=\"CR18\" citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e] vs. 21[\u003cspan additionalcitationids=\"CR20 CR21\" citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e], Z = -6.02, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.001), indicating better functional recovery with the combined block in Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec19\" class=\"Section2\"\u003e \u003ch2\u003eMuscle strength\u003c/h2\u003e \u003cp\u003ePreoperative muscle strength was not significantly different between the FNB and FNB\u0026thinsp;+\u0026thinsp;IPACK groups, (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026gt;\u0026thinsp;0.05). Moreover, At 24 hours postoperative, the FNB\u0026thinsp;+\u0026thinsp;IPACK group had significantly greater muscle strength than the FNB group (2[\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e] vs. 3[\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e], Z = -2.189, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.029). At 48 hours, this difference persisted, with the FNB group showing more pronounced weakness (2[\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e] vs. 3[\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e], Z = -2.46, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.014) in Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec20\" class=\"Section2\"\u003e \u003ch2\u003eRange of motion\u003c/h2\u003e \u003cp\u003eBoth groups had similar preoperative ROM with no significant difference (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026gt;\u0026thinsp;0.05). At 24 hours postoperative, the FNB\u0026thinsp;+\u0026thinsp;IPACK group showed significantly better ROM than the FNB group (90[90\u0026ndash;95] vs. 90[86.25-90], \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.026). By 48 hours, this difference was more pronounced (92.5[90\u0026ndash;95] vs. 90[85-93.75], \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.001) in Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec21\" class=\"Section2\"\u003e \u003ch2\u003eAnesthesia pump\u003c/h2\u003e \u003cp\u003eAnesthesia consumption was lower in the FNB\u0026thinsp;+\u0026thinsp;IPACK group at 24 hours (3[\u003cspan additionalcitationids=\"CR4\" citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e] vs. 4.5[\u003cspan additionalcitationids=\"CR4 CR5\" citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e], Z = -3.08, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.002) and 48 hours (1[\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e] vs. 2[\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e], Z= -3.87, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.001), indicating superior pain control and reduced analgesic need in Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e.\u003c/p\u003e \u003c/div\u003e"},{"header":"Discussion","content":"\u003cp\u003eOur study revealed that the FNB\u0026thinsp;+\u0026thinsp;IPACK group reduced pain levels both while walking and at rest within the first 8, 24, and 48 hours postoperative and experienced significantly less pain compared to the FNB group alone. A review by M. Biehl et al revealed that the FNB\u0026thinsp;+\u0026thinsp;IPACK group had better results in NRS score, pain at rest and during movement; and ambulation distance on POD 0, POD 1, and POD 2 [\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e]. However, A. S. Deis et al found that the FNB\u0026thinsp;+\u0026thinsp;IPACK group had a significantly shorter hospital stay than the FNB group [\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e].\u003c/p\u003e \u003cp\u003ePostoperative ROM was a crucial metric for evaluating outcomes and served as an indicator of the associated muscle strength of the knee [\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e]. An additional significant finding in D\u0026uuml;ndar et al was a better ROM in the IPACK block group at early 24 hours postoperative compared to genicular block and the control group [\u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e]. Nevertheless, FNB could lead to quadriceps muscle weakness, which may increase the risk of falls [\u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e33\u003c/span\u003e, \u003cspan citationid=\"CR34\" class=\"CitationRef\"\u003e34\u003c/span\u003e]. The IPACK block delivers pain relief without causing a reduction in muscle strength by precisely blocking the sensory endings in the posterior part of the knee while leaving the motor components of the tibial and peroneal nerves unaffected [\u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e35\u003c/span\u003e]. Li, D., et al reported better outcomes such as muscle strength and ROM when IPACK was combined with other regional anesthesia techniques [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. Under El-Emam et al reported that compared with ACB alone, IPACK\u0026thinsp;+\u0026thinsp;ACB provided greater muscle strength. [\u003cspan citationid=\"CR36\" class=\"CitationRef\"\u003e36\u003c/span\u003e]. A study by Hsu et al revealed that combining FNB\u0026thinsp;+\u0026thinsp;IPACK block for 30 minutes before anesthesia, reduced opioid usage, facilitating early functional recovery. Moreover, immediate motor block assessment after general anesthesia was not feasible because patients were unconscious [\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eIn this study, FNB\u0026thinsp;+\u0026thinsp;IPACK group demonstrated faster TUG times, better muscle strength, improved ROM, and lower anesthesia pump usage than those who received only FNB. Hussein et al reported that the TUG test was used to assess ambulation early at 12 and 24 hours postoperative which showed FNB group experienced better pain control than the IPACK group [\u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e37\u003c/span\u003e]. The TUG test, along with postoperative walking distance, served as a direct indicator of lower limb mobility [\u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e38\u003c/span\u003e]. As reported by many studies, FNB affected the quadriceps muscle, which led to the inability to ambulate early postoperative, they found that FNB was associated with a significantly longer TUG than ACB [\u003cspan citationid=\"CR39\" class=\"CitationRef\"\u003e39\u003c/span\u003e].\u003c/p\u003e \u003cdiv id=\"Sec23\" class=\"Section2\"\u003e \u003ch2\u003eLimitation\u003c/h2\u003e \u003cp\u003eThis single-center observational study may have selection bias. It did not assess anesthesia side effects or chronic pain, focusing on short-term outcomes within 48 hours. Future multicenter studies should evaluate long-term function and pain management.\u003c/p\u003e \u003c/div\u003e"},{"header":"Conclusion","content":"\u003cp\u003eThe early postoperative in TKA for 24 and 48 hours compared with FNB alone, the FNB\u0026thinsp;+\u0026thinsp;IPACK technique is associated with better pain management and improved functional outcomes. This study revealed superior functional outcomes without compromised motor function, including greater muscle strength, range of motion, and shorter hospital stays. It promotes recovery and faster rehabilitation. It also optimizes mobility, which increases patient satisfaction. The overall quality of care has improved, contributing to better clinical practice.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cp\u003eFNB: Femoral nerve block\u003c/p\u003e\n\u003cp\u003eTKA: Total knee arthroplasty\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eIPACK: Infiltration between the popliteal artery and the capsule of the knee\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eVAS:\u0026nbsp;Visual Analog Scale\u003c/p\u003e\n\u003cp\u003eTUG: Timed Up and Go\u003c/p\u003e\n\u003cp\u003eMMT: Manual muscle testing\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eROM: Range of motion\u003c/p\u003e\n\u003cp\u003eWJX: Wen Juan Xing\u003c/p\u003e\n\u003cp\u003ePACU: The Post-anesthesia Care Unit\u003c/p\u003e\n\u003cp\u003ePA: Popliteal artery\u0026nbsp;\u003c/p\u003e\n\u003cp\u003ePV: Popliteal vein\u003c/p\u003e\n\u003cp\u003eNI: Needle injection\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eFN: Femoral nerve\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eFA: Femoral artery\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eFV: Femoral vein\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eFI: Fascia iliaca\u003c/p\u003e\n\u003cp\u003eFL: Fascia lata\u003c/p\u003e\n\u003cp\u003eLA: Local anesthesia\u003c/p\u003e\n\u003cp\u003ePO: Postoperative\u003c/p\u003e\n\u003cp\u003ePOD: Postoperative day\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eIQR: Interquartile range\u003c/p\u003e\n\u003cp\u003eMdn: Median\u0026nbsp;\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eJoshi, G.P. and B.O. 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Silver, and E.J. Gallagher, \u003cem\u003eReliability of the visual analog scale for measurement of acute pain.\u003c/em\u003e Academic emergency medicine, 2001. \u003cstrong\u003e8\u003c/strong\u003e(12): p. 1153-1157.\u003c/li\u003e\n\u003cli\u003ePodsiadlo, D. and S. Richardson, \u003cem\u003eThe timed \u0026ldquo;Up \u0026amp; Go\u0026rdquo;: a test of basic functional mobility for frail elderly persons.\u003c/em\u003e Journal of the American geriatrics Society, 1991. \u003cstrong\u003e39\u003c/strong\u003e(2): p. 142-148.\u003c/li\u003e\n\u003cli\u003eShumway-Cook, A., S. Brauer, and M. Woollacott, \u003cem\u003ePredicting the probability for falls in community-dwelling older adults using the Timed Up \u0026amp; Go Test.\u003c/em\u003e Physical therapy, 2000. \u003cstrong\u003e80\u003c/strong\u003e(9): p. 896-903.\u003c/li\u003e\n\u003cli\u003eCuthbert, S.C. and G.J. Goodheart Jr, \u003cem\u003eOn the reliability and validity of manual muscle testing: a literature review.\u003c/em\u003e Chiropractic \u0026amp; osteopathy, 2007. \u003cstrong\u003e15\u003c/strong\u003e(1): p. 4.\u003c/li\u003e\n\u003cli\u003eBrennan, P.T., et al., \u003cem\u003eRehabilitation outcomes for total knee arthroplasties: continuous adductor canal block versus continuous femoral nerve block.\u003c/em\u003e Geriatric Orthopaedic Surgery \u0026amp; Rehabilitation, 2018. \u003cstrong\u003e9\u003c/strong\u003e: p. 2151458518756190.\u003c/li\u003e\n\u003cli\u003eHsu, Y.-P., et al., \u003cem\u003eEfficacy and safety of femoral nerve block for the positioning of femur fracture patients before a spinal block\u0026ndash;a systematic review and meta-analysis.\u003c/em\u003e PLoS One, 2019. \u003cstrong\u003e14\u003c/strong\u003e(5): p. e0216337.\u003c/li\u003e\n\u003cli\u003eButterworth, J.F., D.C. Mackey, and J.D. Wasnick, \u003cem\u003eMorgan \u0026amp; Mikhail\u0026apos;s clinical anesthesiology\u003c/em\u003e. 2013.\u003c/li\u003e\n\u003cli\u003eHadzic, A. and Nysora, \u003cem\u003eNYSORA Nerve Block Manual: First Edition\u003c/em\u003e. 2022: NYSORA, Incorporated.\u003c/li\u003e\n\u003cli\u003eMittal, R. and E. Vermani, \u003cem\u003eFemoral nerve blocks in fractures of femur: variation in the current UK practice and a review of the literature.\u003c/em\u003e Emergency Medicine Journal, 2014. \u003cstrong\u003e31\u003c/strong\u003e(2): p. 143-147.\u003c/li\u003e\n\u003cli\u003eUSRA. \u003cem\u003eUSRA-Femoral Nerve Block. (n.d.)\u003c/em\u003e. Available from: https://usra.ca/regional-anesthesia/specific-blocks/lower-limb/femoralnerveblock.php.\u003c/li\u003e\n\u003cli\u003eJerry D. Vloka, A.H., and Philippe Gautier. \u003cem\u003eFemoral Nerve Block \u0026ndash; landmarks and nerve stimulator technique. NYSORA. \u003c/em\u003e. 2022, May 3; Available from: https://www.nysora.com/techniques/lower-extremity/femoral-nerve-block/#:~:text=Sensory%20block%20is%20asses\u003cbr\u003esed,the%20table%29.\u0026amp;text=and%20medial%20aspect%20of,the%20table%29.\u0026amp;\u003cbr\u003etext=aspect%20of%20the%20lower,the%20table%29.\u0026amp;text=asking%20the%20pa\u003cbr\u003etient%20to,the%20table%29.\u003c/li\u003e\n\u003cli\u003eSanjay Sinha, M. \u003cem\u003eHow I Do It: Infiltration Between Popliteal Artery and Capsule of Knee (iPACK). ASRA pain medicine \u003c/em\u003e2020, May 3; Available from: https://www.asra.com/news-publications/asra-newsletter/newsletter-item/asra-news/2020/05/03/how-i-do-it-infiltration-between-popliteal-art.\u003c/li\u003e\n\u003cli\u003eSinha, S.K., A. Clement, and A.-M. Surette, \u003cem\u003eInfiltration between the popliteal artery and capsule of the knee (iPACK): essential anatomy, technique, and literature review.\u003c/em\u003e Current Anesthesiology Reports, 2019. \u003cstrong\u003e9\u003c/strong\u003e: p. 474-478.\u003c/li\u003e\n\u003cli\u003eMaria Fernanda Rojas Gomez, M.a.V.W.C., MD, FRCPC, FRCA. \u003cem\u003eiPACK Block\u003c/em\u003e. 1997; Available from: https://usra.ca/regional-anesthesia/specific-blocks/lower-limb/iPACK.php.\u003c/li\u003e\n\u003cli\u003eVolkmar, A.J., et al., \u003cem\u003eCruciate substituting implants in primary total knee arthrop\u003c/em\u003e\u003cem\u003elasty.\u003c/em\u003e Advances in Orthopaedics, 2022. \u003cstrong\u003e2022\u003c/strong\u003e(1): p. 2676715.\u003c/li\u003e\n\u003cli\u003eGrass, J.A., \u003cem\u003ePatient-controlled analgesia.\u003c/em\u003e Anesthesia \u0026amp; Analgesia, 2005. \u003cstrong\u003e101\u003c/strong\u003e(5S): p. S44-S61.\u003c/li\u003e\n\u003cli\u003eBiehl, M., et al., \u003cem\u003eThe safety and efficacy of the IPACK block in primary total knee arthroplasty: a retrospective chart review.\u003c/em\u003e Canadian Journal of Anesthesia/Journal canadien d\u0026apos;anesth\u0026eacute;sie, 2020. \u003cstrong\u003e67\u003c/strong\u003e: p. 1271-1273.\u003c/li\u003e\n\u003cli\u003eDeis, A., T. Pham, and S. Orebaugh, \u003cem\u003eThe Utility of iPACK Block in Anterior Cruciate Reconstruction Surgery: A Retrospective Study.\u003c/em\u003e Knowledge and Views of Common Citizens Regarding Ambulatory Surgery: 80 A Pilot International Survey, 2022: p. 86.\u003c/li\u003e\n\u003cli\u003eMutsuzaki, H., et al., \u003cem\u003eTarget range of motion for rehabilitation after total knee arthroplasty.\u003c/em\u003e Journal of Rural Medicine, 2017. \u003cstrong\u003e12\u003c/strong\u003e(1): p. 33-37.\u003c/li\u003e\n\u003cli\u003eD\u0026uuml;ndar, A., et al., \u003cem\u003eComparison of the popliteal artery and the capsule of the posterior knee (IPACK) block and the genicular nerve block in primary total knee arthroplasty: A prospective randomized trial.\u003c/em\u003e Saudi Medical Journal, 2024. \u003cstrong\u003e45\u003c/strong\u003e(3): p. 279.\u003c/li\u003e\n\u003cli\u003eThobhani, S., et al., \u003cem\u003eNovel regional techniques for total knee arthroplasty promote reduced hospital length of stay: an analysis of 106 patients.\u003c/em\u003e Ochsner Journal, 2017. \u003cstrong\u003e17\u003c/strong\u003e(3): p. 233-238.\u003c/li\u003e\n\u003cli\u003eLayera, S., et al., \u003cem\u003eMotor-sparing nerve blocks for total knee replacement: a scoping review.\u003c/em\u003e Journal of clinical anesthesia, 2021. \u003cstrong\u003e68\u003c/strong\u003e: p. 110076.\u003c/li\u003e\n\u003cli\u003eKim, D.H., et al., \u003cem\u003eAddition of infiltration between the popliteal artery and the capsule of the posterior knee and adductor canal block to periarticular injection enhances postoperative pain control in total knee arthroplasty: a randomized controlled trial.\u003c/em\u003e Anesthesia \u0026amp; Analgesia, 2019. \u003cstrong\u003e129\u003c/strong\u003e(2): p. 526-535.\u003c/li\u003e\n\u003cli\u003eEl-Emam, E.-S.M., \u003cem\u003eUltrasound-guided adductor canal block versus combined adductor canal and infiltration between the popliteal artery and the posterior capsule of the knee block for osteoarthritis knee pain.\u003c/em\u003e Anesthesia Essays and Researches, 2020. \u003cstrong\u003e14\u003c/strong\u003e(1): p. 127-131.\u003c/li\u003e\n\u003cli\u003eHussein, M.M., et al., \u003cem\u003eComparison between Ultrasound Guided Femoral Nerve Block versus IPACK Block in Patients Undergoing Total Knee Replacement on Postoperative Ambulation and Pain: A randomised controlled clinical trial.\u003c/em\u003e Sri Lankan Journal of Anaesthesiology, 2024. \u003cstrong\u003e32\u003c/strong\u003e(2).\u003c/li\u003e\n\u003cli\u003eBohannon, R.W., \u003cem\u003eReference values for the timed up and go test: a descriptive meta-analysis.\u003c/em\u003e Journal of geriatric physical therapy, 2006. \u003cstrong\u003e29\u003c/strong\u003e(2): p. 64-68.\u003c/li\u003e\n\u003cli\u003eHegazy, N.A. and S.S. Sultan, \u003cem\u003eComparison between effects of adductor canal block and femoral nerve block on early postoperative course in total knee arthroplasty: a prospective double-blind, randomized controlled study.\u003c/em\u003e Ain-Shams J Anaesthesiol, 2015. \u003cstrong\u003e8\u003c/strong\u003e(1): p. 124.\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":true,"highlight":"","institution":"Second Affiliated Hospital of Chongqing Medical University","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Femoral nerve block (FNB), IPACK block, TKA, Pain control, Regional anesthesia","lastPublishedDoi":"10.21203/rs.3.rs-6313558/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6313558/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground \u003c/strong\u003eThis study aimed to assess the effectiveness of combining FNB with an IPACK, compared with FNB alone, for early postoperative pain management after total knee arthroplasty (TKA). This novel technique may significantly improve posterior knee pain control and potentially lead to earlier and better functional outcomes for patients.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMaterials and methods \u003c/strong\u003eThis prospective observational study was conducted between September 2023 and June 2024. The initial 40 consecutive patients received FNB+IPACK, and the subsequent 40 received FNB alone. All patients were evaluated with the visual analog scale (VAS) for pain; the Timed Up \u0026amp; Go (TUG) test for walking and balance; the manual muscle testing (MMT) for muscle strength; range of motion (ROM) for joint flexibility; and anesthesia consumption for preoperative and postoperative pain recorded at 8, 24, and 48 hours. This study assessed various analgesic techniques for pain management and functional outcomes.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults \u003c/strong\u003eThe FNB+IPACK group experienced significantly lower postoperative pain levels at 8, 24, and 48 hours compared with the FNB group (\u003cem\u003eP \u003c/em\u003e\u0026lt; 0.001). Resting pain was significant at the first 8 hours. At 24 hours, the walking VAS score was 3[2-3], with a TUG time of 22[21-23] (both \u003cem\u003eP \u003c/em\u003e\u0026lt; 0.001). By 48 hours, the walking VAS score decreased to 1[1-1.75], and the TUG time improved to 18[17-19] (both \u003cem\u003eP \u003c/em\u003e\u0026lt; 0.001), reflecting continued pain reduction and increased mobility.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusions\u003c/strong\u003e The\u003cstrong\u003e \u003c/strong\u003eFNB+IPACK technique was an excellent analgesic strategy for the TKA postoperative period without adverse effects on motor function.\u003c/p\u003e","manuscriptTitle":"Efficacy of early postoperative ultrasound-guided femoral nerve block (FNB) combined with an infiltration block between the popliteal artery and the capsule of the knee (IPACK) compared to FNB alone for total knee arthroplasty (TKA)","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-03-27 08:28:28","doi":"10.21203/rs.3.rs-6313558/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"9e1f9445-40e9-4243-84d9-bade558e461e","owner":[],"postedDate":"March 27th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[{"id":46254642,"name":"Orthopedic Surgery"}],"tags":[],"updatedAt":"2025-05-14T21:53:19+00:00","versionOfRecord":[],"versionCreatedAt":"2025-03-27 08:28:28","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-6313558","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6313558","identity":"rs-6313558","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}