Pain After Total Knee ArthroplastyNCT07231692
Comparison of BiFeS + ACB and IPACK + ACB Block Combinations for Postoperative Pain After Total Knee Arthroplasty
An observational study of Pain After Total Knee Arthroplasty and Pain, Postoperative, run by Karabuk University at 1 site in Turkey (Türkiye).
Trial summary
This prospective observational study will compare the postoperative analgesic efficacy of two multimodal regional anesthesia combinations routinely used after total knee arthroplasty (TKA) performed under spinal anesthesia. Read more about this study
- Who is it for?
- Ages 18 to 80 yearsHealthy volunteers can take part
- Conditions the study is for
- Pain After Total Knee Arthroplasty, Pain, Postoperative, Arthroplasty, Replacement, Knee
- Type of treatment
- Injection or infusion
- How many people
- 60 participants
- Where
- 1 siteTurkey (Türkiye)
- Study dates
- 15 Oct 2025to 31 Jan 2026
- Phase
- Observational
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 80 years
- All sexes
- Healthy volunteers accepted
- Adult, Older adult
Study population: This study will include adult patients aged 18-80 years undergoing elective unilateral total knee arthroplasty (TKA) under spinal anesthesia at Karabük Training and Research Hospital. Eligible participants will have ASA physical status I-III and be capable of using patient-controlled analgesia (PCA). Patients will be prospectively observed as part of routine multimodal analgesia including either BiFeS + ACB or IPACK + ACB block combinations for postoperative pain management.
Who may be able to join
- Adults aged 18-80 years scheduled for elective unilateral total knee arthroplasty (TKA) under spinal anesthesia
- ASA physical status I-III
- Eligible for and capable of using patient-controlled analgesia (PCA)
- Provided written informed consent
Who cannot join
- Chronic opioid use for more than four weeks before surgery
- Presence of chronic pain conditions (e.g., migraine, fibromyalgia)
- History of alcohol or drug abuse
- Known allergy or hypersensitivity to local anesthetics or opioids
- Severe organ dysfunction (e.g., significant hepatic or renal disease)
- Revision or bilateral knee arthroplasty
Show all 12Show fewer
- Contraindications to regional anesthesia
- Preexisting neuropathy or prior femoral vascular surgery on the operated side.
- Infection near the injection site (e.g., osteomyelitis, septic joint).
- Contraindication to spinal anesthesia (e.g., refusal, coagulopathy, use of anticoagulants or antiplatelet agents) or inability to understand NRS.
- Severe psychiatric or cognitive disorders (e.g., psychosis, dementia) that prevent cooperation or pain assessment
- Pregnant or breastfeeding women
Trial locations and contacts
1 site in 1 country.
Turkey (Türkiye)1 site
Karabuk Training and Research Hospital, Department of Anesthesiology and Reanimation
Karabük, Karabük Province, 78200
About this study
Official title: Comparative Evaluation of Biceps Femoris Short Head (BiFeS) and Adductor Canal Block and Interspace Between the Popliteal Artery and Capsule of the Knee (IPACK) and Adductor Canal Block Combinations for Postoperative Pain After Total Knee Arthroplasty
This prospective observational study will compare the postoperative analgesic efficacy of two multimodal regional anesthesia combinations routinely used after total knee arthroplasty (TKA) performed under spinal anesthesia. The study will observe patient groups who receive, as part of standard clinical practice, either the Biceps Femoris Short Head (BiFeS) block combined with the Adductor Canal Block (ACB) or the Interspace Between the Popliteal Artery and the Capsule of the Knee (IPACK) block combined with the Adductor Canal Block (ACB). The research team will not assign, perform, or direct any blocks; all regional anesthesia procedures will be administered independently by anesthesiologists experienced in ultrasound-guided regional anesthesia as part of routine care.
Postoperative pain will be observed and documented using the Numeric Rating Scale (NRS) at multiple time points within the first 24 hours. Opioid consumption will be recorded based on intravenous patient-controlled analgesia (PCA) data, and the need for rescue analgesia will be noted. Additional postoperative observations will include functional recovery, quality of recovery scores, and the incidence of adverse events.
Postoperative pain will be evaluated using the Numeric Rating Scale (NRS) at multiple time points within the first 24 hours. Opioid consumption will be recorded through intravenous patient-controlled analgesia (PCA), and the need for rescue analgesia will be assessed. Additional postoperative observations will include functional recovery, quality of recovery scores, and the incidence of adverse events.
Read the detailed description
This prospective, single-center, observational study will be conducted at Karabük Training and Research Hospital. This is an observational study. Participants are not assigned to any intervention by the research team. All regional anesthesia blocks are performed as part of routine clinical practice, and the investigators only collect data related to outcomes. No interventions are administered because of study participation. The research team does not perform, modify, or direct any clinical procedures; all blocks are performed independently as part of routine care.
The study population will include adults aged 18-80 years undergoing elective unilateral total knee arthroplasty (TKA) under spinal anesthesia. All eligible patients will receive routine multimodal analgesia and will undergo one of two commonly used regional anesthesia combinations:
Biceps Femoris Short Head (BiFeS) block + Adductor Canal Block (ACB)
Interspace Between the Popliteal Artery and the Capsule of the Knee (IPACK) block + Adductor Canal Block (ACB)
The choice of block combination will be determined by the attending anesthesiologist as part of standard clinical practice. The research team will not influence clinical decisions and will only record perioperative and postoperative data.
Regional Anesthesia Techniques (Routine Care Descriptions)
IPACK Block: The patient will remain in the supine position with the knee flexed 30-45°. A 3.5-6 MHz convex US probe will be placed over the popliteal fossa to visualize the popliteal artery at the femoral condyle level in the short axis. A 22G, 100 mm needle will be advanced in-plane from lateral to medial, and the tip will be positioned between the popliteal artery and femoral condyle. After negative aspiration, 25 mL 0.25% bupivacaine will be slowly injected.The aim is to provide effective posterior knee analgesia by blocking the sensory branches without motor impairment.
BiFeS Block: With the patient in the supine position, the potential space between the lateral supracondylar line of the femur and the short head of the BF muscle will be identified under US guidance. A 22G, 100 mm echogenic needle will be advanced in-plane, and 25 mL 0.25% bupivacaine will be injected. All blocks will be performed by anesthesiologists experienced in ultrasound-guided regional anesthesia.
ACB: ACB will also be performed in the same session using 15 mL 0.25% bupivacaine beneath the sartorius muscle under US guidance.
Anesthesia and Analgesia Approach
All patients will undergo spinal anesthesia as part of routine care. Postoperative analgesia will include multimodal medications used in standard practice at the study center, as well as intravenous patient-controlled analgesia (PCA) when required. Pain intensity will be assessed using the Numeric Rating Scale (NRS), an 11-point scale ranging from 0 (no pain) to 10 (worst imaginable pain). Opioid use will be calculated in morphine milligram equivalents (MME).
Outcome Assessments
Postoperative outcomes will include cumulative opioid consumption at 12 and 24 hours, pain scores at predefined time points, quality of recovery using the Quality of Recovery-15 (QoR-15) questionnaire, postoperative nausea and vomiting (PONV) scores, block performance time, time to first mobilization, functional evaluation with the Timed Up and Go (TUG) test, block-related and opioid-related complications, and total length of hospital stay.
- Medical subject headings
- Pain, Postoperative
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
| Study group | Role | What they receive |
|---|---|---|
| Group BiFeS | Adductor canal block and BiFeS block ( 15 ml %0.25 bupivacaine and 25 ml %0.25 bupivacaine) + IV morphine patient-controlled analgesia (PCA) | |
| Group IPACK | Adductor canal block and IPACK block ( 15 ml %0.25 bupivacaine and 25 ml %0.25 bupivacaine) + IV morphine patient-controlled analgesia (PCA) |
What is being measured
The primary outcome is the main question the study is designed to answer.
Cumulative opioid consumption in the first 24 hours after surgery
Morphine consumption in the first 24 hours after surgery will be measured. Patients will be able to request opioids via a PCA device when their NRS score is ≥ 4.
Measured: Postoperative day 1
Secondary outcomes (12)
Cumulative opioid consumption in the first 12 hours after surgery
Morphine consumption in the first 12 hours after surgery will be measured. Patients will be able to request opioids via a PCA device when their NRS score is ≥ 4.
Measured: postoperative 12th hour
Postoperative pain scores
Pain status at rest and while activity will be assessed by numeric rating scale (NRS) score at 0, 3, 6, 12, 18 and 24 hours after surgery. In addition, the time until the first analgesic requirement will be recorded. The NRS is an 11-point numeric scale that ranges from 0 to 10.
Measured: Postoperative day 1
Block performance time
The duration of block performance will be recorded for BiFeS, ACB, and IPACK procedures. Time will be measured in seconds from the placement of the ultrasound probe on the skin to the completion of local anesthetic injection.
Measured: İntraoperative period
The Quality of Recovery-15 (QoR-15) score
Patient recovery quality and satisfaction will be assessed using the QoR-15 questionnaire at 24 hours postoperatively and at discharge. Higher scores indicate better recovery (QoR-15 score [0-150]).
Measured: 24 hours postoperatively and postoperative day 2-4
The postoperative nausea and vomiting (PONV) scores and the number of patients requiring antiemetic medication
The severity of postoperative nausea and vomiting (PONV) will be assessed using a descriptive verbal rating scale at 0, 3, 6, 12, 18 and 24 hours after extubation. If a score of 3 or more, ondansetron 4 mg IV will be administered and will repeat after 8 hours if required (The PONV scale is 0 = no nausea; 1 = slight nausea; 2 = moderate nausea; 3 = vomiting once; and 4 = vomiting more than once).
Measured: Postoperative day 1
Time of first analgesic request
Time at which the first analgesic is requested
Measured: Postoperative day 1
Number of patients requiring rescue analgesia
Number of patients who required additional rescue analgesics (IV tramadol 100 mg) despite PCA use will be recorded.
Measured: Postoperative day 1
Block-related complications
Complications related to the block procedure, such as local bleeding, hematoma, infection, or local anesthetic systemic toxicity (LAST), will be recorded.
Measured: Postoperative day 7
Opioid-related side effects
Adverse effects including pruritus, sedation, fatigue, or respiratory depression associated with opioid use will be documented.
Measured: Postoperative day 7
Timed Up and Go (TUG) test duration
The time (in seconds) taken for the patient to rise from a chair, walk 3 meters, return, and sit down will be recorded as a measure of functional mobility.
Measured: Postoperative day 1
Time to first mobilization
Time elapsed from the end of surgery to the patient's first mobilization (standing and walking with physiotherapist assistance) will be recorded.
Measured: Postoperative day 1 and postoperative day 2-4
Length of hospital stay
Total time from entry to the operating room until discharge from the hospital will be recorded.
Measured: From surgery to postoperative day 2-4
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted17 Nov 2025
- Study start15 Oct 2025
- Primary completion30 Jan 2026
- Study completion31 Jan 2026
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Pain After Total Knee ArthroplastyStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Cohort
- Time perspective
- Prospective
- Enrolment
- 60 participants (actual)
Sponsor and investigators
- Lead sponsor
- Karabuk University
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Elif Sarikaya Ozel, Karabuk University
- Investigators
- Elif Sarikaya Özel, M.D., Principal investigator, Karabuk Training and Research Hospital, Department of Anesthesiology and Reanimation
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07231692
- Sponsor's protocol ID
- BiFeS2025/2462
- Status last verified
- Jan 2026
- First submitted
- 13 Nov 2025
- Last updated
- 3 Feb 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 3 Feb 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Comparative Evaluation of Biceps Femoris Short Head (BiFeS) and Adductor Canal Block and Interspace Between the Popliteal Artery and Capsule of the Knee (IPACK) and Adductor Canal Block Combinations for Postoperative Pain After Total Knee Arthroplasty
- ClinicalTrials.gov ID
- NCT07231692
- Acronym / sponsor ID
- BiFeS2025/2462
- Study type
- Observational
- Recruitment status
- Completed
- Enrolment
- 60 participants (actual)
- Lead sponsor
- Karabuk UniversityUniversity, hospital or other
- Study start
- 15 Oct 2025 (actual)
- Primary completion
- 30 Jan 2026 (actual)
- Study completion
- 31 Jan 2026 (actual)
- First posted
- 17 Nov 2025 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This prospective observational study will compare the postoperative analgesic efficacy of two multimodal regional anesthesia combinations routinely used after total knee arthroplasty (TKA) performed under spinal anesthesia. The study will observe patient groups who receive, as part of standard clinical practice, either the Biceps Femoris Short Head (BiFeS) block combined with the Adductor Canal Block (ACB) or the Interspace Between the Popliteal Artery and the Capsule of the Knee (IPACK) block combined with the Adductor Canal Block (ACB). The research team will not assign, perform, or direct any blocks; all regional anesthesia procedures will be administered independently by anesthesiologists experienced in ultrasound-guided regional anesthesia as part of routine care.
Postoperative pain will be observed and documented using the Numeric Rating Scale (NRS) at multiple time points within the first 24 hours. Opioid consumption will be recorded based on intravenous patient-controlled analgesia (PCA) data, and the need for rescue analgesia will be noted. Additional postoperative observations will include functional recovery, quality of recovery scores, and the incidence of adverse events.
Postoperative pain will be evaluated using the Numeric Rating Scale (NRS) at multiple time points within the first 24 hours. Opioid consumption will be recorded through intravenous patient-controlled analgesia (PCA), and the need for rescue analgesia will be assessed. Additional postoperative observations will include functional recovery, quality of recovery scores, and the incidence of adverse events.
Detailed description
This prospective, single-center, observational study will be conducted at Karabük Training and Research Hospital. This is an observational study. Participants are not assigned to any intervention by the research team. All regional anesthesia blocks are performed as part of routine clinical practice, and the investigators only collect data related to outcomes. No interventions are administered because of study participation. The research team does not perform, modify, or direct any clinical procedures; all blocks are performed independently as part of routine care.
The study population will include adults aged 18-80 years undergoing elective unilateral total knee arthroplasty (TKA) under spinal anesthesia. All eligible patients will receive routine multimodal analgesia and will undergo one of two commonly used regional anesthesia combinations:
Biceps Femoris Short Head (BiFeS) block + Adductor Canal Block (ACB)
Interspace Between the Popliteal Artery and the Capsule of the Knee (IPACK) block + Adductor Canal Block (ACB)
The choice of block combination will be determined by the attending anesthesiologist as part of standard clinical practice. The research team will not influence clinical decisions and will only record perioperative and postoperative data.
Regional Anesthesia Techniques (Routine Care Descriptions)
IPACK Block: The patient will remain in the supine position with the knee flexed 30-45°. A 3.5-6 MHz convex US probe will be placed over the popliteal fossa to visualize the popliteal artery at the femoral condyle level in the short axis. A 22G, 100 mm needle will be advanced in-plane from lateral to medial, and the tip will be positioned between the popliteal artery and femoral condyle. After negative aspiration, 25 mL 0.25% bupivacaine will be slowly injected.The aim is to provide effective posterior knee analgesia by blocking the sensory branches without motor impairment.
BiFeS Block: With the patient in the supine position, the potential space between the lateral supracondylar line of the femur and the short head of the BF muscle will be identified under US guidance. A 22G, 100 mm echogenic needle will be advanced in-plane, and 25 mL 0.25% bupivacaine will be injected. All blocks will be performed by anesthesiologists experienced in ultrasound-guided regional anesthesia.
ACB: ACB will also be performed in the same session using 15 mL 0.25% bupivacaine beneath the sartorius muscle under US guidance.
Anesthesia and Analgesia Approach
All patients will undergo spinal anesthesia as part of routine care. Postoperative analgesia will include multimodal medications used in standard practice at the study center, as well as intravenous patient-controlled analgesia (PCA) when required. Pain intensity will be assessed using the Numeric Rating Scale (NRS), an 11-point scale ranging from 0 (no pain) to 10 (worst imaginable pain). Opioid use will be calculated in morphine milligram equivalents (MME).
Outcome Assessments
Postoperative outcomes will include cumulative opioid consumption at 12 and 24 hours, pain scores at predefined time points, quality of recovery using the Quality of Recovery-15 (QoR-15) questionnaire, postoperative nausea and vomiting (PONV) scores, block performance time, time to first mobilization, functional evaluation with the Timed Up and Go (TUG) test, block-related and opioid-related complications, and total length of hospital stay.
Study design
- Observational model
- Cohort
- Time perspective
- Prospective
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Group BiFeS | – | –Adductor canal block and BiFeS block ( 15 ml %0.25 bupivacaine and 25 ml %0.25 bupivacaine) + IV morphine patient-controlled analgesia (PCA) |
| Group IPACK | – | –Adductor canal block and IPACK block ( 15 ml %0.25 bupivacaine and 25 ml %0.25 bupivacaine) + IV morphine patient-controlled analgesia (PCA) |
Who may qualify
- Ages
- 18 to 80 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult, Older adult
- Study population
- This study will include adult patients aged 18-80 years undergoing elective unilateral total knee arthroplasty (TKA) under spinal anesthesia at Karabük Training and Research Hospital. Eligible participants will have ASA physical status I-III and be capable of using patient-controlled analgesia (PCA). Patients will be prospectively observed as part of routine multimodal analgesia including either BiFeS + ACB or IPACK + ACB block combinations for postoperative pain management.
Key inclusion criteria (4 listed)
- Adults aged 18-80 years scheduled for elective unilateral total knee arthroplasty (TKA) under spinal anesthesia
- ASA physical status I-III
- Eligible for and capable of using patient-controlled analgesia (PCA)
- Provided written informed consent
Key exclusion criteria (12 listed)
- Chronic opioid use for more than four weeks before surgery
- Presence of chronic pain conditions (e.g., migraine, fibromyalgia)
- History of alcohol or drug abuse
- Known allergy or hypersensitivity to local anesthetics or opioids
- Severe organ dysfunction (e.g., significant hepatic or renal disease)
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Primary outcome
Cumulative opioid consumption in the first 24 hours after surgery
Time frame: Postoperative day 1
Morphine consumption in the first 24 hours after surgery will be measured. Patients will be able to request opioids via a PCA device when their NRS score is ≥ 4.
12 secondary outcomes
Cumulative opioid consumption in the first 12 hours after surgery
Time frame: postoperative 12th hour
Postoperative pain scores
Time frame: Postoperative day 1
Block performance time
Time frame: İntraoperative period
The Quality of Recovery-15 (QoR-15) score
Time frame: 24 hours postoperatively and postoperative day 2-4
The postoperative nausea and vomiting (PONV) scores and the number of patients requiring antiemetic medication
Time frame: Postoperative day 1
Time of first analgesic request
Time frame: Postoperative day 1
Number of patients requiring rescue analgesia
Time frame: Postoperative day 1
Block-related complications
Time frame: Postoperative day 7
Opioid-related side effects
Time frame: Postoperative day 7
Timed Up and Go (TUG) test duration
Time frame: Postoperative day 1
Time to first mobilization
Time frame: Postoperative day 1 and postoperative day 2-4
Length of hospital stay
Time frame: From surgery to postoperative day 2-4
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 3 Feb 2026.
- Individual participant dataSharing planned: No
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Post-Operative Pain Relief: Zynrelef or Periarticular Injections in RATKA
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NEUROCUPLE™ as an Opioid Alternative Following Total Knee Arthroplasty
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Elif Sarikaya Özel, M.D. principal investigator
Karabuk Training and Research Hospital, Department of Anesthesiology and Reanimation
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Pain After Total Knee Arthroplasty and Pain, Postoperative, run by Karabuk University at 1 site in Turkey (Türkiye).
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 4 inclusion and 12 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 3 Feb 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Turkey (Türkiye). Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Cumulative opioid consumption in the first 24 hours after surgery (time frame: Postoperative day 1). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 3 Feb 2026; AzTrials last refreshed its copy on 26 Oct 2026.