Comparing Local Anesthetic Injections to Nerve Blocks for Pain Control After Total Knee Replacement

NCT07744503 | Completed

• 1 other identifier: EK-S2025-11
• Study Type: interventional
• Target: 78
• Locations: 1 country
• Sites: 1

Brief Summary

Why are we doing this study? People who have knee replacement surgery often feel pain afterward. Doctors use different methods to control this pain. One method is an injection of numbing medicine directly into the knee during surgery, called local infiltration analgesia (LIA). Another method uses a thin tube (catheter) placed near nerves in the leg to continuously deliver numbing medicine, called a nerve block. This study compares these two pain control methods after knee replacement surgery, to find out whether the injection method (LIA) works at least as well as the nerve block method for controlling pain. Who can take part in this study? Adults aged 18 to 90 years who need a first-time (primary) knee replacement because of knee arthritis can take part. Participants must be able to walk before surgery, be in generally stable health, and be able to give informed consent. People with a knee injury (rather than arthritis), people who use a wheelchair, and people unable to give consent were not included. What happens during this study? 78 participants were randomly assigned, like a coin flip, to receive either the injection into the knee (LIA) or the nerve block through a catheter for pain relief after surgery. Both groups also received the same standard pain medicines by mouth or vein as needed. Researchers measured pain levels using a 0-10 pain scale before surgery and at 24, 48, 72, and 96 hours afterward. They also measured knee movement (range of motion), how much extra pain medicine was needed, and how satisfied participants were with their pain control. The study took place at one hospital, the Elisabethinen Hospital in Klagenfurt, Austria, between June 2025 and January 2026.

Conditions

Pain, Postoperative; Osteoarthritis, Knee; Arthroplasty, Replacement, Knee

Keywords

Total Knee Arthroplasty; Local Infiltration Analgesia; Peripheral Nerve Block; Femoral Nerve Block; Sciatic Nerve Block; Postoperative Pain Management; Visual Analogue Scale

Outcome Measures

Primary Outcomes (2)

• Postoperative Pain Intensity at 48 Hours (VAS Score)

  Pain intensity measured with the Visual Analogue Scale (VAS), assessed at rest, at night, and during mobilization 48 hours after total knee arthroplasty. This measure was used to test non-inferiority of LIA versus peripheral regional (femoral/sciatic nerve block) anesthesia against a pre-specified non-inferiority margin.

  8 hours postoperatively

• Postoperative Pain Intensity at 48 Hours (VAS Score)

  Pain intensity measured with the Visual Analogue Scale (VAS), assessed at rest, at night, and during mobilization 48 hours after total knee arthroplasty. This measure was used to test non-inferiority of LIA versus peripheral regional (femoral/sciatic nerve block) anesthesia against a pre-specified non-inferiority margin.

  48 hours postoperatively

Study Arms (2)

Local Infiltration Analgesia (LIA)

EXPERIMENTAL

Participants received intraoperative periarticular local infiltration analgesia consisting of 200 mL ropivacaine (2 mg/mL, first 50 mL discarded), 30 mg ketorolac, and 0.5 mg epinephrine, injected during total knee arthroplasty. All participants additionally received the standardized postoperative oral/intravenous analgesic regimen (diclofenac, hydromorphone, metamizole, paracetamol as needed).

Drug: Local Infiltration Analgesia (Ropivacaine, Ketorolac, Epinephrine)

Peripheral Regional Anesthesia (Femoral and Sciatic Nerve Block)

ACTIVE COMPARATOR

Participants received continuous femoral and sciatic nerve block via perineural catheters. An initial local anesthetic bolus was followed by continuous ropivacaine 0.2% infusion for 48 hours postoperatively (5 mL/h for the first 24 hours, then reduced to 3 mL/h), with patient-controlled boluses available. The same standardized postoperative oral/intravenous analgesic regimen as the LIA group was administered.

Drug: Continuous Femoral and Sciatic Nerve Block (Ropivacaine)

Interventions

Continuous Femoral and Sciatic Nerve Block (Ropivacaine) DRUG

Continuous peripheral regional anesthesia via ultrasound-guided femoral and sciatic nerve catheters, placed intraoperatively. Under general anesthesia, each catheter received an initial bolus of 15 mL mepivacaine 1.5% plus 10 mL ropivacaine 0.375%; under spinal anesthesia, an initial 15 mL normal saline (0.9%) test bolus confirmed catheter position, followed by 10 mL ropivacaine 0.375% once sensory block began to wear off. A continuous perineural infusion of ropivacaine 0.2% was then maintained via infusion pump for 48 hours postoperatively: 5 mL/h for the first 24 hours, reduced to 3 mL/h thereafter. Patients could additionally self-administer a 5 mL bolus every 30 minutes as needed. Catheters and the infusion pump were removed at 48 hours postoperatively.

Peripheral Regional Anesthesia (Femoral and Sciatic Nerve Block)

Local Infiltration Analgesia (Ropivacaine, Ketorolac, Epinephrine) DRUG

Periarticular local infiltration analgesia administered intraoperatively during total knee arthroplasty, comprising 150 mL ropivacaine 2 mg/mL (from a 200 mL preparation, first 50 mL discarded), 30 mg ketorolac (1 mL of 30 mg/mL solution), and 0.5 mg epinephrine hydrochloride (0.5 mL of 1 mg/mL solution). The combined solution was injected periarticularly by the operating surgeon as a single intraoperative dose during wound closure. Total ropivacaine dose did not exceed the maximum recommended dose of 300 mg. No repeat dosing was administered postoperatively for this arm.

Local Infiltration Analgesia (LIA)

Eligibility Criteria

• Age: 18 Years - 90 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Age 18 to 90 years Primary or secondary knee osteoarthritis (gonarthrosis) Scheduled for elective primary total knee arthroplasty (cruciate-retaining implant) Ambulatory prior to surgery (able to walk unassisted) American Society of Anesthesiologists (ASA) physical status I-III Able to provide written informed consent

You may not qualify if:

• Post-traumatic knee arthropathy (trauma-related indication for surgery) Wheelchair use / inability to ambulate preoperatively ASA physical status IV or higher Lack of capacity to provide informed consent (e.g., legal guardianship/procurator required) Planned unicompartmental (hemi-) knee arthroplasty or revision surgery Known allergy or contraindication to the study medications (ropivacaine, ketorolac, or epinephrine)

Sponsors & Collaborators

• Christopher Male: lead
• Elisabethinen Hospital: collaborator

Study Sites (1)

Elisabethinen Krankenhaus Klagenfurt

Klagenfurt, Carinthia, 9020, Austria

Location

Related Publications (4)

• Hu B, Lin T, Yan SG, Tong SL, Yu JH, Xu JJ, Ying YM. Local Infiltration Analgesia Versus Regional Blockade for Postoperative Analgesia in Total Knee Arthroplasty: A Meta-analysis of Randomized Controlled Trials. Pain Physician. 2016 May;19(4):205-14.

  PMID: 27228509 RESULT

• Kerr DR, Kohan L. Local infiltration analgesia: a technique for the control of acute postoperative pain following knee and hip surgery: a case study of 325 patients. Acta Orthop. 2008 Apr;79(2):174-83. doi: 10.1080/17453670710014950.

  PMID: 18484242 RESULT

• Myles PS, Myles DB, Galagher W, Boyd D, Chew C, MacDonald N, Dennis A. Measuring acute postoperative pain using the visual analog scale: the minimal clinically important difference and patient acceptable symptom state. Br J Anaesth. 2017 Mar 1;118(3):424-429. doi: 10.1093/bja/aew466.

  PMID: 28186223 RESULT

• Olsen MF, Bjerre E, Hansen MD, Hilden J, Landler NE, Tendal B, Hrobjartsson A. Pain relief that matters to patients: systematic review of empirical studies assessing the minimum clinically important difference in acute pain. BMC Med. 2017 Feb 20;15(1):35. doi: 10.1186/s12916-016-0775-3.

  PMID: 28215182 RESULT

MeSH Terms

Conditions

Pain, Postoperative; Osteoarthritis, Knee

Interventions

Ropivacaine; Ketorolac; Epinephrine

Condition Hierarchy (Ancestors)

Postoperative Complications; Pathologic Processes; Pathological Conditions, Signs and Symptoms; Pain; Neurologic Manifestations; Signs and Symptoms; Osteoarthritis; Arthritis; Joint Diseases; Musculoskeletal Diseases; Rheumatic Diseases

Intervention Hierarchy (Ancestors)

Anilides; Amides; Organic Chemicals; Aniline Compounds; Amines; Indomethacin; Indoles; Heterocyclic Compounds, 2-Ring; Heterocyclic Compounds, Fused-Ring; Heterocyclic Compounds; Ethanolamines; Amino Alcohols; Alcohols; Biogenic Monoamines; Biogenic Amines; Catecholamines; Catechols; Phenols; Benzene Derivatives; Hydrocarbons, Aromatic; Hydrocarbons, Cyclic; Hydrocarbons

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: SUPPORTIVE CARE
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR INVESTIGATOR
• PI Title: Dr. Christopher Male ,Doctoral Candidate, Department of Sustainable Health Research, Medical University of Graz

Model Details: Participants undergoing primary total knee arthroplasty were randomly allocated in a 1:1 ratio to one of two parallel treatment groups: local infiltration analgesia (LIA) or continuous peripheral regional anesthesia via femoral and sciatic nerve block. Each participant received only one of the two analgesic techniques throughout the perioperative and postoperative study period. Randomization was performed using the institutional randomization tool of the Medical University of Graz.

Study Record Dates

• First Submitted: July 30, 2026
• First Posted: August 4, 2026
• Study Start: June 1, 2025
• Primary Completion: January 31, 2026
• Study Completion: January 31, 2026
• Last Updated: August 4, 2026

Record last verified: 2026-07

Data Sharing

• IPD Sharing: Will not share

Locations

AU (1)