Effects of 10 Versus 20 mL Local Anesthetic for Popliteal Plexus Block on Opioid Consumption, Pain, and Patient-Reported Outcomes After Total Knee Arthroplasty

NCT06908837 | Completed Phase 4 DMC

• 1 other identifier: 2024-520204-26-00
• Study Type: interventional
• Target: 120
• Locations: 1 country
• Sites: 1

Brief Summary

This trial aims to assess the analgesic effect of Popliteal Plexus Block (PPB) with 10 mL versus 20 mL of Bupivacain 5 mg/mL, when applied as an adjunct treatment to a multimodal analgesic regimen following primary total knee arthroplasty. We hypothesize that PPB with 20 mL of local anesthetic reduces 24-hour postoperative opioid consumption (= primary outcome) compared to 10 mL after TKA. Secondary outcome include

• the frequency of 24-hour opioid-free analgesia
• pain intensity at rest and during mobilization
• Manual Muscle Tests and ability to mobilize with crutches six hours after end-of-surgery
• and patients reported outcomes using the Quality of Recovery 15 survey 24 hours after end-of-surgery. Participant will:
• undergo primary total knee arthroplasty in spinal anesthesia.
• recieve a PPB with either 10 mL of Bupivacaine or 20 mL.
• recieve a multimodal analgesic regime including a Femoral Triangle Block.
• Have 10 scored morphine tablets available for self-administration within the first 24 postoperative hours after end-of-surgery.
• be examined by a physiotherapist 6 hours (±1 hour) after end-of-surgery to assess pain scores, manual muscle testing of ankle and knee function, and the ability to mobilize with crutches.
• complete a survey 24 hours after end-of-surgery to assess self-administered morphine intake, pain scores, and Quality of Recovery-15.

Conditions

Total Knee Arthroplasty; Regional Anesthesia; Multimodal Analgesic Approach; Postoperative Opioid-related Complications

Keywords

Popliteal Plexus Block; Total knee arthroplasty; regional anesthesia; optimal analgesic volume; postoperative pain; postoperative opioid consumption; Quality of Recovery 15; Manual Muscle Test; Postoperative mobility

Outcome Measures

Primary Outcomes (1)

• Total opioid consumption, expressed in oral morphine milligram equivalents (MME).

  Combining hospital-administered opioid doses from the patient file and self-reported intake of dispensed morphine tablets.

  From T0 (end-of-surgery time) to T24 (24 hours after end-of-surgery time)

Secondary Outcomes (6)

• No opioid requirement

  From T0 (end-of-surgery time) to T24 (24 hours after end-of-surgery time)

• Pain at rest

  Assessed preoperatively, at T6 (6±1 hours after end-of-surgery time), and at T24 (24 hours after end-of-surgery time).

• Pain during 10 meters walk assisted only by crutches

  Assessed preoperatively, at T6 (6±1 hours after end-of-surgery time), and at T24 (24 hours after end-of-surgery time).

• Early postoperative walking ability

  Assessed at T6 (6±1 end-of-surgery time)

• Postoperative Manual Muscle Test

  Assessed at T6 (6±1 end-of-surgery time)

Study Arms (2)

Popliteal Plexus Block with 20 mL of bupivacaine

EXPERIMENTAL

Drug: Bupivacaine

Popliteal Plexus Block with 10 mL of bupivacaine

ACTIVE COMPARATOR

Drug: Bupivacaine

Interventions

Bupivacaine DRUG

Applied perineurally using a 22-gauge, 80-mm block needle (Temena, Felsberg, Germany) under ultrasound guidance.

Popliteal Plexus Block with 10 mL of bupivacaine; Popliteal Plexus Block with 20 mL of bupivacaine

Eligibility Criteria

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

You may qualify if:

• Scheduled to undergo primary total knee arthroplasty in spinal anesthesia.
• Ability to give their written informed consent after having fully understood the contents of the study.
• American Society of Anesthesiologists (ASA) physical status 1, 2, or 3.

You may not qualify if:

• Patients who cannot read or speak Danish.
• Patients who cannot operate or have access to a smartphone with internet connectivity (required for patient-reported outcome assessment).
• Patients with allergies or intolerance to the medicines used in the study.
• Patients with a consistent daily intake of opioids preoperatively.
• Patients who are dependent on walking aid devices preoperatively.
• Patients suffering from alcohol and/or drug abuse - based on the investigator's assessment.
• BMI \> 40.
• Diagnosed with chronic neurodegenerative disorders.

Sponsors & Collaborators

• Regionshospitalet Silkeborg: lead

Study Sites (1)

Elective Surgery Centre at Silkeborg Regional Hospital

Silkeborg, Denmark Central Region, 8600, Denmark

Location

Related Publications (1)

• Sorensen JK, Jensen MSH, Grevstad U, Nikolajsen L, Runge C. Optimal Analgesic Volume for Popliteal Plexus Block After Total Knee Arthroplasty: A Blinded RCT Protocol. Acta Anaesthesiol Scand. 2025 Jul;69(6):e70057. doi: 10.1111/aas.70057.

  PMID: 40346895 DERIVED

MeSH Terms

Conditions

Pain, Postoperative

Interventions

Bupivacaine

Condition Hierarchy (Ancestors)

Postoperative Complications; Pathologic Processes; Pathological Conditions, Signs and Symptoms; Pain; Neurologic Manifestations; Signs and Symptoms

Intervention Hierarchy (Ancestors)

Anilides; Amides; Organic Chemicals; Aniline Compounds; Amines

Study Officials

• Johan K Sørensen, MD

  Elective Surgery Centre at Silkeborg Regional Hospital, Denmark

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: phase 4
• Allocation: RANDOMIZED
• Masking: QUADRUPLE
• Who Masked: PARTICIPANT, CARE PROVIDER, INVESTIGATOR, OUTCOMES ASSESSOR
• Masking Details: Good-Clinical-Practice monitor is also blinded.
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Principal Investigator

Model Details: This single-centre, blinded, controlled, randomized clinical trial follows a parallel design, with one group receiving a PPB with 10 mL of bupivacaine 5 mg/mL and the other group receiving a PPB with 20 mL of bupivacaine 5 mg/mL. A total of 120 patients will be included and allocated in a 1:1 ratio using computer-generated block randomization (blocks of 10).

Study Record Dates

• First Submitted: March 26, 2025
• First Posted: April 3, 2025
• Study Start: April 7, 2025
• Primary Completion: November 26, 2025
• Study Completion: November 26, 2025
• Last Updated: January 22, 2026

Record last verified: 2026-01

Locations

DK (1)