Postoperative Painacb blockNCT07926373
Proximal, Mid, and Distal Adductor Canal Block for Pain Control After Total Knee Arthroplasty
A study testing Proximal Adductor Canal Block, Mid Adductor Canal Block and Distal Adductor Canal Block in people with Postoperative Pain and Arthroplasty, Replacement, Knee, run by Bursa City Hospital.
Trial summary
The goal of this clinical trial is to learn which level of adductor canal block (proximal, mid, or distal) gives the best pain relief after total knee replacement while preserving leg muscle strength. The study includes adults aged 18-75 having knee replacement under spinal anesthesia. Read more about this study
- Who is it for?
- Ages 18 to 75 years
- Conditions the study is for
- Postoperative Pain, Arthroplasty, Replacement, Knee, Knee Osteoarthritis
- What is being tested?
- Proximal Adductor Canal Block, Mid Adductor Canal Block and Distal Adductor Canal Block
- Type of treatment
- Injection or infusion
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 120 participants
- Where
- No sites listed yet
- Study dates
- 10 Nov 2026to 15 Feb 2027
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
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 75 years
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Age 18 to 75 years
- American Society of Anesthesiologists (ASA) physical status I-III
- Scheduled for elective unilateral total knee arthroplasty
- Surgery planned under spinal anesthesia
- Cognitively able to use a patient-controlled analgesia (PCA) device
- Willing to participate and provided written informed consent
Who cannot join
- Refusal to participate
- Allergy to local anesthetics or history of local anesthetic toxicity
- Allergy to tramadol or other study analgesics
- Coagulopathy
- Inability to appropriately discontinue anticoagulant therapy
- Infection at the injection site
Show all 21Show fewer
- Pre-existing motor or sensory deficit in the operative limb
- Peripheral neuropathy
- Significant diabetes-related neuropathy
- Chronic opioid use
- Regular analgesic or opioid use due to a chronic pain syndrome
- Advanced hepatic failure
- Advanced renal failure
- Severe cardiac disease
- Psychiatric illness or cognitive impairment preventing pain assessment
- Substance or alcohol dependence
- Pregnancy or breastfeeding
- Body mass index (BMI) > 40 kg/m²
- Revision knee arthroplasty
- Bilateral knee arthroplasty
- Contraindication to spinal anesthesia
About this study
Official title: Comparison of the Effects of Ultrasound-Guided Proximal, Mid, and Distal Adductor Canal Block on Postoperative Analgesia, Opioid Consumption, Motor Function, and Quality of Recovery in Patients Undergoing Total Knee Arthroplasty: A Prospective, Randomized, Double-Blind, Controlled Study
The goal of this clinical trial is to learn which level of adductor canal block (proximal, mid, or distal) gives the best pain relief after total knee replacement while preserving leg muscle strength. The study includes adults aged 18-75 having knee replacement under spinal anesthesia.
The main question is: Does the block level change how much opioid (tramadol) patients need in the first 24 hours after surgery?
Participants will be randomly assigned to one of three groups and receive an ultrasound-guided block with 30 mL of 0.25% bupivacaine before surgery. Pain, opioid use, numbness, muscle function, walking ability, side effects, and recovery quality will be assessed for 48 hours after surgery.
Read the detailed description
The adductor canal block (ACB) is widely used for analgesia after total knee arthroplasty because it preserves quadriceps strength better than the femoral nerve block. However, the optimal injection level within the canal is unclear.
In this prospective, randomized, double-blind study, 120 patients will be randomized 1:1:1 to proximal, mid, or distal ACB. All blocks will be performed preoperatively under ultrasound guidance with an in-plane technique, using 30 mL of 0.25% bupivacaine. Spinal anesthesia will then be performed. Postoperative analgesia will be standardized for all patients and will include paracetamol, NSAIDs when appropriate, tramadol via patient-controlled analgesia, and meperidine 50 mg as rescue analgesia.
The anesthesiologist performing the block will not take part in data collection. Patients, outcome assessors, and the statistician will be blinded to group allocation.
- Being tested
- Proximal Adductor Canal Block, Mid Adductor Canal Block, Distal Adductor Canal Block
- Keywords
- Adductor Canal Block, Total Knee Arthroplasty, Opioid Consumption, Saphenous Nerve, Regional Anesthesia
- Medical subject headings
- Pain, Postoperative, Osteoarthritis, Knee
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Proximal Adductor Canal BlockOther
Ultrasound-guided in-plane injection in the proximal subsartorial segment, near the apex of the femoral triangle, where the sartorius muscle begins to cover the femoral artery.
Mid Adductor Canal BlockOther
Ultrasound-guided in-plane injection at the classic mid-thigh level, where the femoral artery lies beneath the sartorius muscle.
Distal Adductor Canal BlockOther
Ultrasound-guided in-plane injection in the distal adductor canal, proximal to the adductor hiatus, where the saphenous nerve begins to separate from the femoral artery.
| Study group | Role | What they receive |
|---|---|---|
| Proximal Adductor Canal Block | Active comparator | Ultrasound-guided adductor canal block performed in the proximal subsartorial segment, near the apex of the femoral triangle, using 30 mL of 0.25% bupivacaine before spinal anesthesia. Receives: Other: Proximal Adductor Canal Block |
| Mid Adductor Canal Block | Active comparator | Ultrasound-guided adductor canal block performed at the classic mid-thigh level, where the femoral artery lies beneath the sartorius muscle, using 30 mL of 0.25% bupivacaine before spinal anesthesia. Receives: Other: Mid Adductor Canal Block |
| Distal Adductor Canal Block | Active comparator | Ultrasound-guided adductor canal block performed in the distal segment of the adductor canal, proximal to the adductor hiatus, using 30 mL of 0.25% bupivacaine before spinal anesthesia. Receives: Other: Distal Adductor Canal Block |
What is being measured
The primary outcome is the main question the study is designed to answer.
Total Tramadol Consumption in the First 24 Hours
Cumulative tramadol consumption (mg) delivered via patient-controlled analgesia (PCA) during the first 24 hours after surgery.
Measured: Postoperative 0-24 hours
Secondary outcomes (4)
Pain Scores at Rest
Pain at rest assessed with the Numeric Rating Scale (NRS; 0 = no pain, 10 = worst imaginable pain).
Measured: Postoperative 0, 1, 2, 4, 8, 12, 24, and 48 hours
Pain Scores During Movement
Pain during standardized knee flexion or active/passive movement assessed with the NRS (0-10).
Measured: Postoperative 0, 1, 2, 4, 8, 12, 24, and 48 hours
Tramadol Consumption at Predefined Intervals
PCA tramadol consumption (mg) in the 0-4, 4-8, 8-24, and 24-48 hour intervals and cumulative 48-hour consumption.
Measured: Postoperative 0-48 hours
Time to First Rescue Analgesic Request
Time (minutes) from the end of surgery to the first administration of rescue analgesia (meperidine 50 mg), given when NRS is 4 or higher or analgesia is inadequate despite PCA.
Measured: Postoperative 0-48 hours
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted9 Nov 2026
- Study start10 Nov 2026 (estimated)
- Primary completion15 Feb 2027 (estimated)
- Study completion15 Feb 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Postoperative PainStudies 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
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Other
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Model description
- Three-arm parallel-group design. Participants are randomized 1:1:1 to proximal, mid, or distal adductor canal block, all using 30 mL of 0.25% bupivacaine.
- Masking
- Single blind
- Who is masked
- Participant
- Enrolment
- 120 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Bursa City Hospital
- Sponsor type
- Other government
- Collaborators
- Ulusoy, Emre, M.D.
- Responsible party
- Principal investigator, Mursel Ekinci, Bursa City Hospital
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07926373
- Sponsor's protocol ID
- BSH17
- Acronym
- acb block
- Status last verified
- Nov 2026
- First submitted
- 3 Nov 2026
- Last updated
- 9 Nov 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
Study at a glance
From the registry record, last updated by the sponsor on 9 Nov 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Comparison of the Effects of Ultrasound-Guided Proximal, Mid, and Distal Adductor Canal Block on Postoperative Analgesia, Opioid Consumption, Motor Function, and Quality of Recovery in Patients Undergoing Total Knee Arthroplasty: A Prospective, Randomized, Double-Blind, Controlled Study
- ClinicalTrials.gov ID
- NCT07926373
- Acronym / sponsor ID
- acb block / BSH17
- Keywords
- Adductor Canal Block, Total Knee Arthroplasty, Opioid Consumption, Saphenous Nerve, Regional Anesthesia
- Study type
- Interventional
- Recruitment status
- Not yet recruiting
- Enrolment
- 120 participants (estimated)
- Lead sponsor
- Bursa City HospitalOther government
- Collaborators
- Ulusoy, Emre, M.D.
- Study start
- 10 Nov 2026 (estimated)
- Primary completion
- 15 Feb 2027 (estimated)
- Study completion
- 15 Feb 2027 (estimated)
- First posted
- 9 Nov 2026 (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.
The goal of this clinical trial is to learn which level of adductor canal block (proximal, mid, or distal) gives the best pain relief after total knee replacement while preserving leg muscle strength. The study includes adults aged 18-75 having knee replacement under spinal anesthesia.
The main question is: Does the block level change how much opioid (tramadol) patients need in the first 24 hours after surgery?
Participants will be randomly assigned to one of three groups and receive an ultrasound-guided block with 30 mL of 0.25% bupivacaine before surgery. Pain, opioid use, numbness, muscle function, walking ability, side effects, and recovery quality will be assessed for 48 hours after surgery.
Detailed description
The adductor canal block (ACB) is widely used for analgesia after total knee arthroplasty because it preserves quadriceps strength better than the femoral nerve block. However, the optimal injection level within the canal is unclear.
In this prospective, randomized, double-blind study, 120 patients will be randomized 1:1:1 to proximal, mid, or distal ACB. All blocks will be performed preoperatively under ultrasound guidance with an in-plane technique, using 30 mL of 0.25% bupivacaine. Spinal anesthesia will then be performed. Postoperative analgesia will be standardized for all patients and will include paracetamol, NSAIDs when appropriate, tramadol via patient-controlled analgesia, and meperidine 50 mg as rescue analgesia.
The anesthesiologist performing the block will not take part in data collection. Patients, outcome assessors, and the statistician will be blinded to group allocation.
Study design
- Primary purpose
- Other
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Single blind (participant)
- Number of arms
- 3
- Model description
- Three-arm parallel-group design. Participants are randomized 1:1:1 to proximal, mid, or distal adductor canal block, all using 30 mL of 0.25% bupivacaine.
| Arm | Type | Receives |
|---|---|---|
| Proximal Adductor Canal Block | Active comparator | Other: Proximal Adductor Canal BlockUltrasound-guided adductor canal block performed in the proximal subsartorial segment, near the apex of the femoral triangle, using 30 mL of 0.25% bupivacaine before spinal anesthesia. |
| Mid Adductor Canal Block | Active comparator | Other: Mid Adductor Canal BlockUltrasound-guided adductor canal block performed at the classic mid-thigh level, where the femoral artery lies beneath the sartorius muscle, using 30 mL of 0.25% bupivacaine before spinal anesthesia. |
| Distal Adductor Canal Block | Active comparator | Other: Distal Adductor Canal BlockUltrasound-guided adductor canal block performed in the distal segment of the adductor canal, proximal to the adductor hiatus, using 30 mL of 0.25% bupivacaine before spinal anesthesia. |
Who may qualify
- Ages
- 18 to 75 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (6 listed)
- Age 18 to 75 years
- American Society of Anesthesiologists (ASA) physical status I-III
- Scheduled for elective unilateral total knee arthroplasty
- Surgery planned under spinal anesthesia
- Cognitively able to use a patient-controlled analgesia (PCA) device
Key exclusion criteria (21 listed)
- Refusal to participate
- Allergy to local anesthetics or history of local anesthetic toxicity
- Allergy to tramadol or other study analgesics
- Coagulopathy
- Inability to appropriately discontinue anticoagulant therapy
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Proximal Adductor Canal BlockUltrasound-guided in-plane injection in the proximal subsartorial segment, near the apex of the femoral triangle, where the sartorius muscle begins to cover the femoral artery. | Other | Proximal Adductor Canal Block |
| Mid Adductor Canal BlockUltrasound-guided in-plane injection at the classic mid-thigh level, where the femoral artery lies beneath the sartorius muscle. | Other | Mid Adductor Canal Block |
| Distal Adductor Canal BlockUltrasound-guided in-plane injection in the distal adductor canal, proximal to the adductor hiatus, where the saphenous nerve begins to separate from the femoral artery. | Other | Distal Adductor Canal Block |
Primary outcome
Total Tramadol Consumption in the First 24 Hours
Time frame: Postoperative 0-24 hours
Cumulative tramadol consumption (mg) delivered via patient-controlled analgesia (PCA) during the first 24 hours after surgery.
4 secondary outcomes
Pain Scores at Rest
Time frame: Postoperative 0, 1, 2, 4, 8, 12, 24, and 48 hours
Pain Scores During Movement
Time frame: Postoperative 0, 1, 2, 4, 8, 12, 24, and 48 hours
Tramadol Consumption at Predefined Intervals
Time frame: Postoperative 0-48 hours
Time to First Rescue Analgesic Request
Time frame: Postoperative 0-48 hours
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 9 Nov 2026.
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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.
The record lists no contact. Use the official record to reach the sponsor.
Questions about this trial
What is this clinical trial studying?
A study testing Proximal Adductor Canal Block, Mid Adductor Canal Block and Distal Adductor Canal Block in people with Postoperative Pain and Arthroplasty, Replacement, Knee, run by Bursa City Hospital.
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 6 inclusion and 21 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: opening soon, as of the sponsor's last update on 9 Nov 2026. Status can change between updates, so confirm with the study contact before making plans.
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?
This study is still under way. Results are not available in the source record yet.
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?
Total Tramadol Consumption in the First 24 Hours (time frame: Postoperative 0-24 hours). 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 9 Nov 2026.