Research Articles | Challenge Journal of Perioperative Medicine

Comparison of ultrasound-guided genicular block vs. intrathecal morphine for postoperative analgesia in patients undergoing knee arthroplasty: A randomised prospective study

Ebru Canakci, Ilker Coskun

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Aim:  Total knee arthroplasty (TKA) is a major orthopedic surgical procedure often necessitating effective postoperative analgesia. This study aimed to compare the analgesic efficacy of ultrasound-guided genicular block (GB) and intrathecal morphine (ITM) in patients undergoing THA under spinal anesthesia.

Method: A prospective, randomized, single-blind study was conducted at Ordu University Training and Research Hospital from October 1, 2022, to April 1, 2023. Eligible patients aged 18 to 90 undergoing knee surgery with spinal anesthesia were randomized into two groups: Group ITM received intrathecal morphine, while Group GB underwent ultrasound-guided triple genicular block. Pain scores, rescue opioid consumption, time to initial mobilization, and Modified Bromage Scale (MBS) scores were assessed at five time points (0, 2, 6, 12, and 24 hours) within the first 24 hours post-surgery.

Results: At the 24-hour mark, cumulative tramadol consumption was significantly lower in Group ITM compared to Group GB (35.45±54.84 vs. 63.37±37.7 mg, respectively, p = 0.028). Group ITM also exhibited statistically lower Numeric Rating Scale (NRS) scores at 12 hours (p = 0.005) but had similar scores at other time points. Additionally, time to first ambulation and MBS scores were consistent across all intervals (p < 0.05).

Conclusions: In patients undergoing knee arthroplasty with spinal anesthesia, those receiving ultrasound-guided genicular blocks demonstrated higher opioid consumption over a 24-hour period compared to those receiving intrathecal morphine. However, regarding postoperative pain scores, both groups exhibited similar outcomes. These findings provide valuable insights into the selection of postoperative analgesic modalities for TKA patients.


knee arthroplasty; genicular block; intrathecal morphine; multimodal analgesia


Ward MM, Dasgupta A. Regional variation in rates of total knee arthroplasty among Medicare beneficiaries. JAMA Netw Open. 2020; 3(4): e203717-e203717.

Weinstein AM, Rome BN, Reichmann WM et al. Estimating the burden of total knee replacement in the United States. J Bone Joint Surg Am. 2013; 95(5): 385-392.

Wang JK, Nauss LA, Thomas JE. Pain relief by intrathecally applied morphine in man. Anesthesiology. 1979; 23(6): 384.

Palmer CM, Emerson S, Volgoropolous D et al.. Dose response relationship of intrathecal morphine for postcesarean analgesia. Anesthesiology. 1999; 90(1): 437–444.

Bengtsson M, Lofstrom JB, Merits H. Postoperative pain relief with intrathecal morphine after major hip surgery. Reg Anesth. 1983; 8(4): 139–143.

Jacobson L, Chabal C, Brody MC. A dose-response study of intrathecal morphine: efficacy, duration, optimal dose and side effects. Anesth Analg. 1988; 67(11): 1082–1088.

Grace D, Bunting H, Milligan KR, Fee JPH. Postoperative analgesia after co-administration of clonidine and morphine by the intrathecal route in patients undergoing hip replacement. Anesthesia and Analgesia. 1995; 80(1): 86–91.

Kaczocha M, Azim S, Nicholson J, et al. Intrathecal morphine administration reduces postoperative pain and peripheral endocannabinoid levels in total knee arthroplasty patients: a randomized clinical trial. BMC Anesthesiol. 2018; 18(1): 1-10.

Lauretti GR, Righeti CC, Mattos AL. Intrathecal ketorolac enhances intrathecal morphine analgesia following total knee arthroplasty. J Anaesthesiol Clin Pharmacol. 2013; 29(4): 503-508.

Miyamoto S, Sugita T, Aizawa T, et al. The effect of morphine added to periarticular multimodal drug injection or spinal anesthesia on pain management and functional recovery after total knee arthroplasty. Journal of Orthopaedic Science. 2018; 23(5): 801–806.

Murphy PM, Stack D, Kinirons B, Laffey JG. Optimizing the dose of intrathecal morphine in older patients undergoing hip arthroplasty. Anesthesia and Analgesia. 2003; 97: 1709–1715.

Kunopart M, Chanthong P, Thongpolswat N, Intiyanaravut T, Pethuahong C. Effects of single shot femoral nerve block combined with intrathecal morphine for postoperative analgesia: a randomized, controlled, dose-ranging study after total knee arthroplasty. J Med Assoc Thai. 2014; 97(2): 195-202.

Kukreja P, Venter A, Mason L, et al. Comparison of Genicular Nerve Block in Combination With Adductor Canal Block in Both Primary and Revision Total Knee Arthroplasty: A Retrospective Case Series. Cureus. 2021; 13(7): e16712.

Caldwell GL Jr, Selepec MA. Reduced Opioid Use After Surgeon-Administered Genicular Nerve Block for Anterior Cruciate Ligament Reconstruction in Adults and Adolescents. HSSJ. 2019; 15(1): 42-50.

Tabur Gümüşkanat Z, Yılmaz C, Karasu D, et al. Comparison of ultrasound guided femoral anterior sciatic nerve block and genicular nerve block for postoperative pain in total knee arthroplasty. Cukurova Med J. 2021; 46(4): 1433-1440.

Soffin EM, Memtsoudis SG. Anesthesia and analgesia for total knee arthroplasty, Minerva Anestesiol, 2018; 84(12) : 1406–1412.

Karageorgos V, Brofidi K, Stefanidou N, et al. Femoral 3-in-1 Nerve Block for Total Knee Replacement, an Analgesic Approach Not to Be Neglected. Single Center Experience and Literature Review, Acta Med Acad, 2022; 51(1): 14–20.

Tang X, Lai Y, Du S, Ning N, Analgesic efficacy of adding the IPACK block to multimodal analgesia protocol for primary total knee arthroplasty: a meta-analysis of randomized controlled trials, J Orthop Surg Res, 2022;17(1): 565.

Zheng FY, Liu YB, Huang H, et al. The impact of IPACK combined with adductor canal block under ultrasound guidance on early motor function after total knee arthroplasty, Braz J Anesthesiol, 2022; 72(1): 110–114.

Akesen S, Akesen B, Atıcı T et al. Comparison of efficacy between the genicular nerve block and the popliteal artery and the capsule of the posterior knee (IPACK) block for total knee replacement surgery: A prospective randomized controlled study.Acta Orthop Traumatol Turc, 2021; 55(2): 134–140.

Fonkoué L, Behets C, Kouassi JÉK et al. Distribution of sensory nerves supplying the knee joint capsule and implications for genicular blockade and radiofrequency ablation: an anatomical study, Surg Radiol Anat, 2019; 41(12): 1461–1471.

Yaşar E, Kesikburun S, Kılıç C et al. Accuracy of Ultrasound-Guided Genicular Nerve Block: A Cadaveric Study, Pain Physician, 2015; 18 (5): 899–904.

Cohen E. Intrathecal morphine: The forgotten child. J Cardiothorac Vasc Anesth. 2013; 27(3): 413-416.

Bernards CM. Recent insights into the pharmacokinetics of spinal opioids and the relevance to opioid selection. Anesthesiology. 2004; 17(5): 441-447.

Ummenhofer WC, Arends RH, Shen DD et al. Comparative spinal distribution and clearance kinetics of intrathecally administered morphine, fentanyl, alfentanil, and sufentanil. Anesthesiology. 2000; 92(3): 739-753.

Sharpe EE, Molitor RJ, Arendt KW et al. Intrathecal Morphine versus Intrathecal Hydromorphone for Analgesia after Cesarean Delivery: A Randomized Clinical Trial. Anesthesiology. 2020; 132(6): 1382-1391.

Thomas A, Miller A, Roughan J et al. Efficacy of Intrathecal Morphine in a Model of Surgical Pain in Rats. PLoS One. 2016; 11(10): e0163909.

Kaczocha M, Azim S, Nicholson J et al. Intrathecal morphine administration reduces postoperative pain and peripheral endocannabinoid levels in total knee arthroplasty patients: a randomized clinical trial. BMC Anesthesiol 2018; 18(1): 27.


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