Comparison of the Analgesic Efficacy of Adductor Canal Block Versus Adductor Canal Plus Biceps Femoris Short Head Block in Patients Undergoing Knee Arthroscopy (bifes knee)

Comparison of the Analgesic Efficacy of Adductor Canal Block Versus Adductor Canal Plus Biceps Femoris Short Head Block in Patients Undergoing Knee Arthroscopy: A Prospective Randomized Controlled Trial

This prospective, randomized, controlled, and multicenter clinical study aims to compare the postoperative analgesic efficacy of two regional anesthesia techniques commonly used in knee arthroscopy: adductor canal block (ACB) and combined adductor canal block plus biceps femoris short head (ACB+BiFeS) block. The study will evaluate postoperative pain control, opioid consumption, adverse effects, hospital stay, and patient satisfaction. Findings will help determine the most effective and safe method for postoperative analgesia in knee arthroscopy patients.

Study Overview

• Status: Completed
• Conditions: Postoperative Pain Management
• Intervention / Treatment: Procedure: Adductor Canal Block (ACB) Only; Procedure: biceps femoris short head block + Adductor Canal Block (ACB)

Detailed Description

Knee arthroscopy is one of the most common orthopedic procedures and is frequently associated with significant postoperative pain. Effective multimodal analgesia is therefore essential to reduce opioid consumption, improve early mobilization, and enhance overall patient recovery. Among the regional anesthesia techniques, the adductor canal block (ACB) is well established as an effective motor-sparing block that provides analgesia to the medial and anterior aspects of the knee. However, patients often continue to experience posterolateral knee pain, which is not consistently relieved by ACB alone.

Recent anatomical and cadaveric studies have described the biceps femoris short head (BiFeS) block as a promising technique for targeting the posterolateral knee compartment. The BiFeS block involves deposition of local anesthetic between the short head of the biceps femoris muscle and the lateral femoral cortex at the supracondylar level. Preliminary findings suggest that this block may provide effective analgesia for the posterolateral knee without causing significant motor impairment.

This prospective, randomized, controlled, multicenter clinical trial is designed to evaluate whether the addition of the BiFeS block to standard ACB improves postoperative analgesia compared with ACB alone in patients undergoing knee arthroscopy under spinal anesthesia. The study will investigate pain scores at rest and during movement, total opioid consumption, side effects, rescue analgesic requirements, and quality of recovery. The dermatomal distribution of the blocks will be optionally assessed using cold testing.

By directly comparing ACB and combined ACB+BiFeS block under standardized perioperative conditions, this study seeks to generate high-quality evidence on the clinical utility of BiFeS as an adjunct technique. The results are expected to guide anesthesiologists in selecting optimal regional analgesia strategies for knee arthroscopy, with the potential to improve patient satisfaction, reduce opioid-related complications, and shorten hospitalization.

• Study Type: Interventional
• Enrollment (Actual): 50
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Turkey (Türkiye)
  • küçükçekmece
    • Istanbul, küçükçekmece, Turkey (Türkiye), 34303
      • Health Science University İstanbul Kanuni Sultan Süleyman Education and Training Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Age ≥ 18 years
• ASA physical status I-III
• Scheduled for elective knee arthroscopy under spinal anesthesia
• Ability to provide written informed consent

Exclusion Criteria:

• Coagulopathy or bleeding diathesis
• Current use of anticoagulant therapy
• Known allergy or contraindication to local anesthetics used in the study
• History of diabetes mellitus with neuropathy or other neuropathic disorders
• Contraindications to regional anesthesia techniques
• Refusal to participate

Study Plan

How is the study designed?

Design Details

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

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Adductor Canal Block (ACB); Participants will undergo ultrasound-guided adductor canal block at the end of surgery under spinal anesthesia.	Procedure: Adductor Canal Block (ACB) Only; Ultrasound-guided injection of 10 mL 0.25% bupivacaine into the adductor canal targeting the femoral artery region, providing motor-sparing analgesia to the medial/anterior knee.
Active Comparator: Adductor Canal Block + Biceps Femoris Short Head Block (ACB+BiFeS); Participants will undergo both adductor canal block and biceps femoris short head block at the end of surgery under spinal anesthesia.	Procedure: biceps femoris short head block + Adductor Canal Block (ACB); Combination of adductor canal block (10 mL 0.25% bupivacaine) and biceps femoris short head block with 25 mL 0.25% bupivacaine, deposited at the interfascial plane between BiFeS muscle and lateral femoral cortex to extend analgesia to the posterolateral knee.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Total Opioid Consumption (Tramadol, mg)	The total dose of tramadol administered via intravenous patient-controlled analgesia (PCA) device within the first 24 hours postoperatively will be recorded in milligrams.	24 hours

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Postoperative Pain with Movement and at rest (NRS)	Pain intensity during knee movement will be assessed using the Numerical Rating Scale (0-10).	At 0, 6, 12, and 24 hours after surgery
Rescue Analgesia Requirement	The number of patients requiring rescue analgesia (IV dexketoprofen 50 mg) will be recorded.	Within the first 24 hours postoperatively
Incidence of Nausea and Vomiting	Presence of nausea/vomiting and the requirement for antiemetic medications will be documented.	Within the first 24 hours postoperatively
Dermatomal Spread of Block	Sensory block distribution will be assessed using a cold test to map dermatomal coverage.	2nd hour postoperatively
Motor Blockade Incidence	Patients will be evaluated for presence or absence of motor weakness attributable to the block.	Within the first 24 hours postoperatively
Quality of Recovery (QOR-15 score)	Patient recovery quality will be assessed using the validated Quality of Recovery 15-item questionnaire (QOR-15). The scale includes 15 items, each scored from 0 to 10, producing a total score ranging from 0 to 150. Minimum score: 0 (poor recovery) Maximum score: 150 (excellent recovery) Interpretation: Higher scores indicate better postoperative recovery.	At 24 hours after surgery

Collaborators and Investigators

• Sponsor: Kanuni Sultan Suleyman Training and Research Hospital
• Investigators: Principal Investigator: Engin ihsan Turan, Specialist, Health Science University İstanbul Kanuni Sultan Süleyman Education and Training Hospital

Study record dates

Study Major Dates

• Study Start (Actual): November 20, 2025
• Primary Completion (Actual): April 3, 2026
• Study Completion (Actual): April 3, 2026

Study Registration Dates

• First Submitted: November 17, 2025
• First Submitted That Met QC Criteria: November 17, 2025
• First Posted (Actual): November 21, 2025

Study Record Updates

• Last Update Posted (Actual): April 7, 2026
• Last Update Submitted That Met QC Criteria: April 5, 2026
• Last Verified: April 1, 2026

More Information

Terms related to this study

• Keywords: regional anesthesia
• Additional Relevant MeSH Terms: Socioeconomic Factors; Population Characteristics; Demography; Family Characteristics; Marital Status; Single Person
• Other Study ID Numbers: Bifes knee

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No