Skip to main content
OpenTrials
Recruiting

NCT Number: NCT06740214

Analgesic Efficacy of Different Liposomal Bupivacaine Doses in the Adductor Canal Block for Total Knee Arthroplasty

Total knee arthroplasty is a commonly performed orthopaedic surgery for the treatment of end-stage osteoarthritis when conservative management becomes ineffective. TKA is associated with significant acute postoperative pain and many patients experience severe postoperative pain despite the use of multimodal analgesia. Poor acute postoperative pain control impacts rehabilitation, prolongs recovery and increases opioid consumption and chronic post-surgical pain.

Liposomal bupivacaine (Exparel, Pacira Pharmaceuticals Inc, Parsippany, New Jersey, USA) is a multivesicular formulation of bupivacaine that prolongs drug release and can extend the duration of analgesia. The adductor canal block (ACB) has been shown to reduce pain intensity and opioid consumption after total knee arthroplasty. The use of liposomal bupivacaine in the adductor canal block has recently been FDA-approved. However, the results of its efficacy from existing clinical trials have been mixed. In addition, the doses in the clinical trials have been different, and the optimal dose for perineural application of liposomal bupivacaine is unclear, including for the adductor canal block.

In this project, the investigators propose to conduct a randomized controlled trial to investigate the effect of different doses of liposomal bupivacaine in the adductor canal block on acute postoperative pain intensity and opioid consumption after robotic assisted total knee arthroplasty. The investigators will also assess secondary outcomes including knee functional scores, chronic pain and quality of recovery.

Recruiting

Interested in participating?

Request Info

Key information

Conditions

Pain, Postoperative Analgesic Effect Dose Response Relationship, Drug Liposomal Bupivacaine Neurologic Manifestations Pain Pathologic Processes Pathological Conditions, Signs and Symptoms Postoperative Complications Signs and Symptoms Total Knee Arthroplasty

Age range

18 year–80 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Phase 3

Primary location

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • ASA I-III
  • Age 18-80 years old
  • Scheduled for elective primary unilateral total knee arthroplasty (TKA) with robotic surgery
  • Able to speak and understand Cantonese or Mandarin or English
  • Able to provide informed oral and written consent

Exclusion criteria

  • Revision TKA
  • Single-stage bilateral TKA
  • Complex primary TKA requiring use of stem/augment/constrained liner
  • Surgeries with significant intraoperative complications which may alter rehabilitation protocol eg collateral ligament injury, fracture requiring fixation
  • Known allergy to opioids, local anaesthetic drugs, paracetamol, non-steroidal anti-inflammatory drugs (NSAIDS) including COX-2 inhibitors
  • History of chronic pain other than chronic knee pain
  • History of immunosuppression
  • Chronic use of glucocorticoids
  • Chronic opioid use (morphine, fentanyl, hydromorphone, ketobemidone, methadone, nicomorphine, oxycodone, or meperidine)
  • History of congestive heart failure (NYHA 2)
  • Alcohol or drug abuse
  • Impaired renal function (defined as effective glomerular filtration rate < 30ml/min/1.73m2
  • Impaired liver function (defined as plasma bilirubin over 34mol/L; international normalized ratio [INR] >= 1.7, alanine aminotransferase [ALT] over 100U/L, aspartate aminotransferase [AST] over 100U/L)
  • Coagulopathy (platelet count <100,000/ml and/or INR >= 1.5) or the use of anticoagulants (not including aspirin) that precludes the use of adductor canal blocks
  • Pre-existing neurological or muscular disorders
  • Psychiatric illness
  • Impaired mental state
  • Pregnancy
  • Local infection
  • On immunosuppressants
  • High body mass index (BMI) (>=40)
  • Patient refusal for regional nerve blocks or to conduct clinical trial

Treatment and study plan

0.5% standard bupivacaine only

Drug

20ml 0.5% standard bupivacaine only

1.33% liposomal bupivacaine with 0.5% standard bupivacaine

Drug

10ml 1.33% liposomal bupivacaine (133mg) plus 10ml 0.5% standard bupivacaine

1.33% liposomal bupivacaine only

Drug

20ml 1.33% liposomal bupivacaine (266mg)

Primary outcomes

  1. Weighted area under curve (AUC) pain score

    Time frame: The first 48 hours after surgery when the patient is at rest

    Pain severity would be rated at rest after surgery using numerical rating scale (NRS) with 0 to 10 where 0=no pain and 10=the worst possible pain

Secondary outcomes

  1. NRS pain scores

    Time frame: from after surgery to postoperative day 7

    NRS pain scores at rest and with movement (active knee flexion) from after surgery to postoperative day (POD) 7, ranging 0-10, with higher scores indicating more severe pain.

  2. Oxynorm consumption

    Time frame: Postoperative day 1-7

    Oxynorm consumption from postoperative day (POD) 1-7

  3. Overall Benefit of Analgesic Score (OBAS)

    Time frame: Postoperative day (POD) 1-7

    Overall Benefit of Analgesic Score (OBAS) from postoperative day (POD) 1-7 (range, 0 [best] to 28 [worst])

  4. Plasma level of bupivacaine and ropivacaine

    Time frame: Blood will be collected during induction, at 12 hours, 24 hours, 48 hours, and 72 hours after ACB.

    Plasma level of bupivacaine and ropivacaine before and after surgery

  5. Quality of Recovery Questionnaire (QoR-9)

    Time frame: Postoperative day 1

    Quality of Recovery Questionnaire (QoR-9) on postoperative day 1, ranging from 0 to 18, with higher scores indicating good recovery after anaesthesia.

  6. Rehabilitation parameters (range of maximal active knee flexion)

    Time frame: While the patient is in hospital from postoperative day 0, day 1, and day 2.

    Range of maximal active knee flexion will be assessed by the physiotherapists while the patient is in hospital.

  7. Rehabilitation parameters (quadricep power)

    Time frame: While the patient is in hospital from postoperative day 0, day 1, and day 2.

    Quadricep power will be assessed by the physiotherapists while the patient is in hospital.

    Ratings:

    0 - no muscle contraction

    • - Move w/o gravity
    • - Raise then drop down immediately
    • - Raise against gravity w/o resistance
    • - Raise against gravity w/some resistance
    • - Raise against gravity w/ full resistance

  8. Rehabilitation parameters (ability to perform straight leg raising)

    Time frame: While the patient is in hospital from postoperative day 0, day 1, and day 2.

    Ability to perform straight leg raising will be assessed by the physiotherapists while the patient is in hospital. Ratings (Yes/ No).

  9. Rehabilitation parameters (walking distance)

    Time frame: While the patient is in hospital from postoperative day 0, day 1, and day 2.

    Walking distance (in metres) will be assessed by the physiotherapists while the patient is in hospital.

  10. Rehabilitation parameters (Duration of hospital stay)

    Time frame: estimated on average of postoperative day 7 at the date of discharge from hospital

    No. of hospitalization days from admission to discharge

  11. Rehabilitation parameters (discharge location)

    Time frame: estimated on average of postoperative day 7 at the date of discharge from hospital

    Home or rehabilitation center

  12. Opioid-related side effects

    Time frame: While the patient is in hospital from postoperative day 0, 1, and 2.

    Presence or absence of pruritus, dizziness, nausea, and vomiting will be recorded.

  13. Potential side effects related to adductor canal block (ACB)

    Time frame: While the patient is in hospital from postoperative day 0, 1, and 2.

    Presence or absence of local anaesthetic toxicity, neurological injury, and intravascular injection will be recorded.

  14. Analgesic block duration

    Time frame: While the patient is in hospital at postoperative day 1

    Measured in time to return of pain (When did your pain relief from the block completely wear off?), time to sensory resolution (When did your numbness completely resolve and return to normal?), and time to motor resolution (When did your arm or hand weakness resolve and return to normal?)

  15. Sensory and motor assessment

    Time frame: While the patient is in hospital from post-block 2 hours, 6 hours, 12 hours, and 24 hours.

    The affected lower limb will be measured.

    Sensory assessment (Sensation to pin prick), rating from 0 (no sensation) to 10 (normal sensation)

    Motor assessment

    • Straight leg raising achieved Ratings (Yes/ No)
    • Quadriceps power

    Ratings:

    0 - no muscle contraction

    • - Move w/o gravity
    • - Raise then drop down immediately
    • - Raise against gravity w/o resistance
    • - Raise against gravity w/some resistance
    • - Raise against gravity w/ full resistance

  16. quality of life (SF12v2)

    Time frame: at 6 weeks and at 3 and 6 months after surgery

    Eight domains of SF-12v2 (HK) are measured on a scale ranging from 0 to 100. A higher domain score indicates a better HRQoL.

  17. Identification Pain Questionnaire for Neuropathic Pain (ID-NeP)

    Time frame: at 6 weeks, 3 months and 6 months postoperatively

    Neuropathic pain will be assessed using Identification Pain Questionnaire for Neuropathic Pain (ID-NeP), consisting of six items: "Yes" answers to questions 1-5 were given a score of 1, while "yes" answer to question 6 scored -1. "No" answers to questions 1-5 were given a score of 0, while "yes" answer to question 6 scored 0.

  18. Knee Society Knee Function Score

    Time frame: at 6 weeks, 3 months and 6 months postoperatively

    Knee Society Knee Function Score at 6 weeks, 3 months and 6 months postoperatively, from 0 to 100 with lower scores being indicative of worse knee conditions and higher scores being indicative of better knee conditions.

  19. Chronic post-surgical pain

    Time frame: at 6 weeks, 3 months and 6 months postoperatively

    The presence or absence of chronic post-surgical pain, pain scores if present.

Study contacts

Contact information is provided by the study sponsor or research team.

Stanley S.C. WONG, MD (HKU)

CONTACT

[email protected]

(852) 2255 3303

Sponsors and collaborators

Lead sponsor

The University of Hong Kong

Other

Registry information

Official study title

Analgesic Efficacy of Different Liposomal Bupivacaine Doses in the Adductor Canal Block for Total Knee Arthroplasty: a Randomized Controlled Trial

Important dates

Study start
2025
Primary completion
2027
Study completion
2028
First posted
Dec 18, 2024
Registry last updated
Nov 24, 2025

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

Related clinical trials

Published trials that share one or more normalized conditions with this study.