Comparison of Analgesic Efficacy and Impact on Motor Function in Knee Replacement Surgery: 0.1% Naropeine Tri-block Versus 0.5% Naropeine iPACK Saphenous Block - A Prospective Randomised Trial (ProBlocs)

Over the last two decades, perioperative analgesia has evolved. Spinal and epidural anaesthesia, once common, have been gradually phased out due to their side effects. The femoral block combined with the sciatic block, possibly with a perineural catheter, is now the gold standard for ensuring prolonged, high-quality analgesia. However, these blocks can cause muscle weakness in the quadriceps, limiting patients' functional recovery.

To optimise functional rehabilitation, recent techniques favour more distal and selective blocks, such as the adductor canal (saphenous) block and the iPACK, which allow effective anaesthesia to be maintained whilst preserving motor function. However, these blocks do not always guarantee complete analgesia and may require additional blocks.

The hypothesis of the current study is based on the idea that a proximal block targeting the femoral, obturator and sciatic nerves, administered with a low concentration of naropeine (0.1%), could provide more effective analgesia than a 0.5% saphenous iPACK block, whilst preserving motor function The originality of our approach in the current study lies in the use of dissociative proximal blocks performed with low concentrations of local anaesthetics, aimed at effectively covering the innervation of the knee whilst preserving motor function.

The expected outcomes of this research are to optimise analgesic management for patients undergoing functional orthopaedic knee surgery, to promote early postoperative walking rehabilitation, to reduce the risk of chronic pain following knee arthroplasty, and to provide evidence to guide anaesthetic and post-surgical rehabilitation practices

Study Overview

• Status: Not yet recruiting
• Conditions: Knee Surgery
• Intervention / Treatment: Other: Tri-bloc; Other: iPACK saphène

• Study Type: Interventional
• Enrollment (Estimated): 120
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Dr Emilie ELLIES DROUAUD; Phone Number: +33 (0)679324918; Email: elliese64@gmail.com

Study Locations

• France
  • Paris, France, 75016
    • Clinique Jouvenet
    • Contact: Dr Emilie ELLIES DROUAUD; Phone Number: +33 (0)679324918; Email: elliese64@gmail.com

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Age > 18 years;
• Patients scheduled for total knee replacement (TKR);
• ASA (American Society of Anesthesiologists) class 1 to 3;
• Patient who is able to understand the information relating to the study, read the information leaflet and agree to sign the informed consent form;
• Enrolment iin the French healthcare system.

Exclusion Criteria:

• Patients with an ASA score > 3;
• Patients with a chronic pain condition requiring regular prescription pain relief, such as osteoarthritis, fibromyalgia, neuropathic pain or rheumatoid arthritis;
• Patients with a major anxiety disorder (APAIS score);
• Patients with a history of algodystrophy;
• Pregnant or breastfeeding women;
• History or evidence of any other clinically significant disorder, condition or disease which, in the investigator's opinion, would pose a risk to patient safety or interfere with the assessment, procedures or completion of the study;
• Participation in any other clinical trial during the duration of the study;
• Patients under guardianship or curatorship or subject to deprivation of liberty.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Other
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Experimental group (tri-block); Anaesthesia of femoral block, obturator block and popliteal sciatic block performed using 0.1% naropeine, combined with intraoperative intravenous administration of 0.15 mg/kg of dexamethasone.	Other: Tri-bloc; Injection of 0.1% naropeine for a femoral, obturator and sciatic block (Tri-block technique), combined with intraoperative intravenous administration of 0.15 mg/kg of dexamethasone.
Active Comparator: Control Group (iPACK saphène); Anaesthesia of iPACK block and saphenous block performed using 0.5% naropine, also combined with intraoperative intravenous administration of 0.15 mg/kg of dexamethasone.	Other: iPACK saphène; Injection of 0.5% naropeine for an iPACK and saphenous nerve block (iPACK saphenous arm), combined with intraoperative intravenous administration of 0.15 mg/kg of dexamethasone.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Total morphine consumption in the postoperative period at 72 hours during the hospital stay	from knee surgery (enrollment) to 3 days post-surgery

Collaborators and Investigators

• Sponsor: GCS Ramsay Santé pour l'Enseignement et la Recherche

Study record dates

Study Major Dates

• Study Start (Estimated): September 30, 2026
• Primary Completion (Estimated): September 30, 2026
• Study Completion (Estimated): December 31, 2027

Study Registration Dates

• First Submitted: May 5, 2026
• First Submitted That Met QC Criteria: May 5, 2026
• First Posted (Actual): May 11, 2026

Study Record Updates

• Last Update Posted (Actual): May 11, 2026
• Last Update Submitted That Met QC Criteria: May 5, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Other Study ID Numbers: COS-RGDS-2024-12-033

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No