Comparison of Analgesic Efficacy of Infiltration Between the Popliteal Artery and Capsule of the Knee (IPACK) Versus Biceps Femoris Short Head Block Combined With Adductor Canal Block in Total Knee Arthroplasty
Trial Snapshot
- Phase
- Not Applicable
- Status
- Recruiting
- Sponsor
- Enrollment
- 78
- Locations
- 1
- Primary Endpoint
- Cumulative 24-hour Opioid Consumption (Morphine Equivalent Dose)
Study Overview
Brief Summary
Total knee arthroplasty (TKA) is associated with severe postoperative pain that delays mobilization, prolongs hospital stay, and reduces patient satisfaction. Regional analgesia techniques have gained prominence due to their opioid-sparing effects and favorable complication profiles compared to general anesthesia. While adductor canal block (ACB) effectively manages anterior knee pain with preserved motor function, posterior knee pain remains a challenge. IPACK (Infiltration between the Popliteal Artery and Capsule of the Knee) and the Biceps Femoris Short Head (BiFeS) block are techniques targeting posterior capsule innervation without causing motor block.This prospective study aims to compare the postoperative analgesic efficacy of ultrasound-guided ACB+IPACK versus ACB+BiFeS block combinations in patients undergoing TKA under spinal anesthesia. Patients (ASA I-III, age 18-80, BMI ≤35) will be randomized into two groups (n=39 each). Primary outcomes include NRS pain scores at rest and on movement, and opioid consumption at 0, 1, 3, 6, 12, 18, and 24 hours postoperatively. Secondary outcomes include time to first mobilization, motor block incidence, quadriceps muscle strength assessment, PONV, and quality of recovery (QoR-15).
Detailed Description
Total knee arthroplasty (TKA) is a widely performed surgical intervention for end-stage knee osteoarthritis and other debilitating knee conditions. Severe postoperative pain following TKA delays early mobilization and rehabilitation, prolongs hospital stay, reduces patient satisfaction, and increases complication risk. Regional analgesia techniques have emerged as the preferred approach due to their ability to reduce opioid consumption, minimize opioid-related side effects (nausea, vomiting, respiratory depression, constipation), and preserve motor function. Ultrasound guidance further improves block success rates and reduces the local anesthetic volume required.
Optimal postoperative analgesia in TKA requires consideration of the complex innervation of the knee joint. The anterior compartment is primarily innervated by branches of the femoral nerve, while the posterior capsule is supplied by branches of the sciatic nerve. Adductor Canal Block (ACB) reduces anterior knee pain by blocking the saphenous nerve and branches of the obturator nerve while preserving quadriceps strength compared to femoral nerve block; however, it may be insufficient alone for controlling posterior capsule pain. The IPACK block (Infiltration between the Popliteal Artery and Capsule of the Knee) addresses posterior knee pain by depositing local anesthetic between the popliteal artery and knee capsule, blocking sensory innervation of the posterior capsule without causing motor block. The Biceps Femoris Short Head (BiFeS) block is a novel ultrasound-guided technique targeting nerve branches innervating the posterolateral knee capsule, aiming to reduce posterior knee pain while preserving motor function.
Study Design:
This is a prospective, randomized, observational study conducted at Hitit University Erol Olçok Training and Research Hospital. Patients will be randomized into two groups by an investigator not directly involved in the study:
Group P (ACB+IPACK): Adductor canal block combined with IPACK block (n=39) Group B (ACB+BiFeS): Adductor canal block combined with Biceps Femoris Short Head block (n=39)
Study Design
- Study Type
- Interventional
- Allocation
- Randomized
- Intervention Model
- Parallel
- Primary Purpose
- Supportive Care
- Masking
- Single (Participant)
Eligibility Criteria
- Ages
- 18 Years to 80 Years (Adult, Older Adult)
- Sex
- All
- Accepts Healthy Volunteers
- No
Inclusion Criteria
- •Scheduled for primary total knee arthroplasty surgery
- •ASA physical status classification I-III
- •Hemodynamically stable
- •Age ≥ 18 years and ≤ 80 years
- •BMI ≤ 35 kg/m²
- •Signed written informed consent form
Exclusion Criteria
- •Revision total knee arthroplasty surgery
- •Simultaneous bilateral total knee arthroplasty
- •BMI > 40 kg/m²
- •ASA physical status classification 4-5
- •Inability to perform NRS pain scoring
- •Known allergy to local anesthetics
- •Pregnancy or breastfeeding
- •Age < 18 or > 80 years
- •Uncontrolled anxiety disorder
- •Alcohol or drug dependency
- •Neuromuscular disease or peripheral nerve disease
- •High-dose opioid use within 3 days prior to surgery
- •Widespread chronic pain syndrome
- •Diabetes mellitus
- •Hepatic or renal insufficiency
- •Coagulation disorders
- •Current use of anticoagulant medications
- •Infection at the peripheral nerve block needle insertion site
- •Refusal to participate in the study
Arms & Interventions
ACB+IPACK Group
ACB+IPACK Group:
Patients receiving ultrasound-guided adductor canal block (15 mL of 0.25% bupivacaine) combined with IPACK block (25 mL of 0.25% bupivacaine) for postoperative analgesia following total knee arthroplasty under spinal anesthesia.
Intervention: ACB+IPACK Group (Procedure)
ACB+BiFeS Group
ACB+BiFeS Group:
Patients receiving ultrasound-guided adductor canal block (15 mL of 0.25% bupivacaine) combined with Biceps Femoris Short Head block (25 mL of 0.25% bupivacaine) for postoperative analgesia following total knee arthroplasty under spinal anesthesia.
Intervention: ACB+BiFeS Group (Procedure)
Outcomes
Primary Outcomes
Cumulative 24-hour Opioid Consumption (Morphine Equivalent Dose)
Time Frame: 24 hours postoperative
Total postoperative opioid consumption will be calculated as morphine-equivalent dose (mg) over the first 24 hours. Tramadol administered via patient-controlled analgesia (PCA) and rescue fentanyl (25 mcg IV for NRS ≥4) will be recorded and converted into morphine equivalents. The cumulative total opioid consumption at 24 hours will be reported.
Secondary Outcomes
No secondary outcomes reported
Investigators
Merve Yagiz Baldiran
Principal Investigator
Hitit University