Continuous Adductor Canal Block (CACB) Combined With İnfiltration Between the Popliteal Artery and Capsule of the Knee (iPACK) Block vs Continuous Adductor Canal Block Alone After Total Knee Arthroplasty

September 28, 2026 updated by: Furkan Tontu, Başakşehir Çam & Sakura City Hospital

Comparison of the Effects of iPACK Block Combined With Continuous Adductor Canal Block Versus Continuous Adductor Canal Block Alone on Postoperative Analgesia, Early Mobilization, and Length of Hospital Stay in Total Knee Arthroplasty Cases

This study compares the effects of adding an infiltration between the popliteal artery and capsule of the knee (iPACK) block to a continuous adductor canal block (CACB) versus continuous adductor canal block alone on postoperative analgesia, opioid consumption, early mobilization, and length of hospital stay in patients undergoing total knee arthroplasty. This is a prospective, randomized, double-blind study with 54 patients allocated 1:1 into two groups.

Study Overview

Status

Not yet recruiting

Conditions

Intervention / Treatment

Detailed Description

Severe postoperative pain occurs in up to 58% of patients after total knee arthroplasty. Peripheral nerve blocks are an effective component of multimodal analgesia, and the continuous adductor canal block (CACB) has become a preferred technique because it provides sensory blockade while sparing motor function of the quadriceps, allowing earlier ambulation compared to femoral nerve block. However, CACB does not address posterior knee pain, which can be targeted by the iPACK (infiltration between the popliteal artery and capsule of the knee) block, a technique that blocks terminal sensory branches of the tibial and peroneal nerves without motor blockade.

In this study, patients scheduled for total knee arthroplasty will be randomized 1:1 (using randomizer.org) to receive either CACB alone (Group 2) or CACB combined with a single-injection iPACK block (Group 1). CACB will be maintained via a perineural catheter connected to a patient-controlled analgesia (PCA) pump delivering 0.1% bupivacaine. Rescue analgesia will be provided with intravenous tramadol (50 mg, max 300 mg/day) when the numeric rating scale (NRS) pain score exceeds 4.

Pain scores (NRS 0-10), total analgesic and opioid consumption, hemodynamic parameters, time to first mobilization (assessed via the Timed Up and Go test), patient satisfaction, and length of hospital stay will be recorded at baseline and at 1, 3, 6, 12, and 24 hours postoperatively by an anesthesiologist blinded to group allocation, different from the anesthesiologist who performed the block.

Study Type

Interventional

Enrollment (Estimated)

54

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact Backup

Study Locations

  • Turkey (Türkiye)
    • Istanbul
      • Başakşehir, Istanbul, Turkey (Türkiye), 34480
        • Basaksehir Çam Ve Sakura City Hospital, İstanbul, Türkiye
        • Contact:
        • Contact:
        • Principal Investigator:
          • Furkan TONTU, MD
        • Sub-Investigator:
          • Muzaffer GENCER, MD
        • Sub-Investigator:
          • Murat Y Mersin, MD

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

18 years to 75 years (Adult, Older Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Description

Inclusion Criteria:

  • Patients of either sex
  • Aged 18 to 75 years
  • American Society of Anesthesiologists (ASA) physical status I, II, or III
  • Voluntary participation
  • Fully oriented and able to cooperate with postoperative assessments

Exclusion Criteria:

  • ASA physical status IV or V
  • Patients who decline to participate
  • Pediatric patients
  • Active infection at the block site
  • Chronic pain or regular analgesic use
  • Coagulation disorders
  • Inability to cooperate with postoperative pain assessment
  • Known allergy to local anesthetics
  • Neuropathy or myopathy in the operated extremity
  • Revision arthroplasty cases

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Double

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Group 1 (CACB + iPACK)

Continuous adductor canal block (catheter, PCA with 0.1% bupivacaine) plus a single-injection iPACK block (0.25% bupivacaine 20 mL)
Procedure: IPACK block

Single injection of 0.25% bupivacaine 20 mL between the popliteal artery and posterior knee capsule, performed under ultrasound guidance

Procedure: Continuous adductor canal block (CACB)

Perineural catheter placement in the adductor canal with PCA-delivered 0.1% bupivacaine (5-7 mL basal rate, 5 mL bolus, 30-min lockout) for 24 hours postoperatively
Active Comparator: Group 2 (CACB Alone)

Continuous adductor canal block alone (catheter, PCA with 0.1% bupivacaine)
Procedure: Continuous adductor canal block (CACB)

Perineural catheter placement in the adductor canal with PCA-delivered 0.1% bupivacaine (5-7 mL basal rate, 5 mL bolus, 30-min lockout) for 24 hours postoperatively

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Postoperative Pain Score (Numeric Rating Scale)
Time Frame: Baseline and postoperative hours 1, 3, 6, 12, and 24

Pain intensity assessed using the Numeric Rating Scale (NRS, 0-10; 0 = no pain, 10 = worst pain imaginable)
Baseline and postoperative hours 1, 3, 6, 12, and 24

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Total Opioid Consumption
Time Frame: Postoperative 24 hours

Total rescue analgesic (tramadol) consumption via intravenous (IV) administration
Postoperative 24 hours
Total Local Anesthetic Consumption
Time Frame: Postoperative 24 hours

Total bupivacaine consumed via patient-controlled analgesia (PCA) pump
Postoperative 24 hours
Time to First Mobilization
Time Frame: Postoperative 24 hours

Time to first unassisted ambulation/movement, assessed via the Timed Up and Go (TUG) test
Postoperative 24 hours
Length of Hospital Stay
Time Frame: From surgery to discharge (up to approximately 1 week)

Number of days from surgery to discharge
From surgery to discharge (up to approximately 1 week)
Patient Satisfaction Score
Time Frame: Postoperative 24 hours

Satisfaction rated on a 4-point scale (1 = not satisfied, 2 = Slightly satisfied, 3 = Satisfied, 4 = very satisfied)
Postoperative 24 hours
Systolic Blood Pressure
Time Frame: Baseline and postoperative hours 1, 3, 6, 12, and 24

Systolic blood pressure measured in mmHg
Baseline and postoperative hours 1, 3, 6, 12, and 24
Diastolic Blood Pressure
Time Frame: Baseline and postoperative hours 1, 3, 6, 12, and 24

Diastolic blood pressure measured in mmHg
Baseline and postoperative hours 1, 3, 6, 12, and 24
Mean Arterial Blood Pressure
Time Frame: Baseline and postoperative hours 1, 3, 6, 12, and 24

Mean arterial blood pressure (MAP) measured in mmHg
Baseline and postoperative hours 1, 3, 6, 12, and 24
Heart Rate
Time Frame: Baseline and postoperative hours 1, 3, 6, 12, and 24

Heart rate measured in beats per minute
Baseline and postoperative hours 1, 3, 6, 12, and 24
Peripheral Oxygen Saturation
Time Frame: Baseline and postoperative hours 1, 3, 6, 12, and 24

Peripheral oxygen saturation (SpO2) measured as a percentage
Baseline and postoperative hours 1, 3, 6, 12, and 24
Block-Related Complications
Time Frame: Throughout study participation (up to 24 hours postoperatively)

Incidence of complications associated with the regional block techniques (e.g., nerve injury, infection)
Throughout study participation (up to 24 hours postoperatively)

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Başakşehir Çam & Sakura City Hospital

Investigators

  • Principal Investigator: Furkan TONTU, MD, BAŞAKŞEHİR ÇAM VE SAKURA ŞEHİR HASTANESİ
  • Study Director: Muzaffer GENCER, MD, BAŞAKŞEHİR ÇAM VE SAKURA ŞEHİR HASTANESİ
  • Study Director: Murat Y Mersin, MD, BAŞAKŞEHİR ÇAM VE SAKURA ŞEHİR HASTANESİt

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Estimated)

September 25, 2026

Primary Completion (Estimated)

December 4, 2026

Study Completion (Estimated)

December 11, 2026

Study Registration Dates

First Submitted

September 15, 2026

First Submitted That Met QC Criteria

September 28, 2026

First Posted (Actual)

October 1, 2026

Study Record Updates

Last Update Posted (Actual)

October 1, 2026

Last Update Submitted That Met QC Criteria

September 28, 2026

Last Verified

September 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • BSH-ANES-MYM-02

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

IPD Plan Description

Individual participant data will not be shared beyond what is reported in publications resulting from this study.

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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