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Enrolling by Invitation

NCT Number: NCT07584915

Pilot Study on EXPAREL as an Intra-articular Posteromedial Surgeon Administered (IPSA) Block vs. Local Infiltration Analgesia in Knee Replacement Surgery

The study aims to test the safety and effectiveness of two different surgeon-administered methods of the anesthesia medication EXPAREL during knee replacement surgery. This study will not determine whether one method is better than the other, but will instead help the study investigator decide if both methods can provide an equal amount of pain relief.

The main question this study aims to answer is:

Will EXPAREL provide an equal amount of pain relief for patients who receive EXPAREL via Intra-articular Posteromedial Surgeon Administered (IPSA) Block and patients that receive EXPAREL via Local Infiltration Analgesia (LIA)?

Following their surgery, participants will be asked to report their pain level on their treated knee using a numerical rating scale (NRS) between 0 to 10. In addition to their pain level, participants will report any medications used for pain relief and will mark specific regions on an image to indicate where they experience pain.

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Key information

Conditions

Total Knee Arthroplasty Total Knee Arthroplasty Recovery

Age range

18 year and older

Sex eligibility

All sexes

Study type

Interventional

Phase

Phase 4

Primary location

Cedars-Sinai Medical Center

Los Angeles, California, 90048, United States

Who can participate

Healthy volunteers accepted: No

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

Inclusion criteria

  • 18 years of age or older
  • Scheduled to undergo total knee arthroplasty (TKA) under spinal anesthesia
  • Primary indication for TKA is degenerative osteoarthritis of the knee
  • Able to provide informed consent, adhere to the study schedule, and complete all study assessments
  • Body Mass Index (BMI) ≥18 and <40 kg/m2

Exclusion criteria

  • Allergy, hypersensitivity, intolerance, or contraindication to any of the study medications for which an alternative is not named in the protocol (e.g., amide-type local anesthetics, opioids, bupivacaine HCl, NSAIDs)
  • Planned concurrent surgical procedure
  • Undergoing knee surgery for a single area of the knee or a revision surgery
  • History of knee replacement surgery within the past 6 months
  • History of, suspected, or known addiction to or abuse of illicit drug(s), prescription medicine(s), or alcohol within the past 2 years
  • Previous participation in an EXPAREL study
  • Uncontrolled anxiety, schizophrenia, or other psychiatric disorder that, in the opinion of the Investigator, could interfere with study assessments or compliance
  • Currently pregnant, nursing, or planning to become pregnant during the study
  • Any individual who, per standard of care, is excluded from the surgery due to possibility of pregnancy.
  • Male participant in a sexually active relation with pregnant or breastfeeding partner
  • Clinically significant medical disease that, in the opinion of the Investigator, would make participation in a clinical study inappropriate.
  • Any use of marijuana [including Tetrahydrocannabinol (THC) and Cannabidiol (CBD)] within 30 days prior to randomization, or planned use during the course of the study
  • Chronic opioid use within 30 days prior to surgery

Treatment and study plan

Intra-articular Posteromedial Surgeon Administered (IPSA) Block with LIA

Procedure

The IPSA block is a specific surgeon technique which involves providing an injection of EXPAREL to the back of the knee, reaching into the joint space to provide pain relief. This arm will also receive the LIA procedure.

Local Infiltration Analgesia (LIA)

Procedure

The local infiltration analgesia (LIA) procedure involves the administration of anesthesia with the use of several needle sticks to areas surrounding the knee joint.

Bupivacaine liposome injectable suspension (IPSA block)

Drug

Group 1 will be given an IPSA block using 10 mL of EXPAREL mixed with 10 mL of bupivacaine HCl 0.5%. An injection around the knee joint will be given as well utilizing a cocktail of: 10 mL of EXPAREL, 10 mL of bupivacaine HCl 0.5%, and 40 mL normal saline.

Bupivacaine liposome injectable suspension (LIA)

Drug

Group 2 will be given LIA with EXPAREL 20 mL (266 mg) mixed with 20 mL bupivacaine HCL 0.5% and 80 mL normal saline (total volume of 120 mL).

Primary outcomes

  1. Post-Operative Pain Scores

    Time frame: Study participants will report Numerical Rating Scale (NRS) pain intensity scores throughout various timepoints between 0 to 72 hours post-surgery.

    The primary outcome measure will be the Numerical Rating Scale (NRS) pain intensity scores reported by study participants. These results will be compared between both treatment groups.

Sponsors and collaborators

Lead sponsor

Cedars-Sinai Medical Center

Other

Collaborators

  • Pacira Pharmaceuticals, Inc

Registry information

Official study title

A Prospective, Single-Center, Randomized, Pilot Study to Assess the Clinical Effectiveness of EXPAREL as an Intra-articular Posteromedial Surgeon Administered (IPSA) Block Compared to Local Infiltration Analgesia in Subjects Undergoing Primary Unilateral Total Knee Arthroplasty

Acronym: CRS-121

Important dates

Study start
2026
Primary completion
2026
Study completion
2026
First posted
May 13, 2026
Registry last updated
May 13, 2026

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.

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