An interventional study of Proximal Adductor Canal Block and Mid Adductor Canal Block in Postoperative Pain, Arthroplasty, Replacement, Knee and Knee Osteoarthritis, sponsored by Bursa City Hospital. Not yet recruiting. Open to participants aged 18 Years to 75 Years. Per ClinicalTrials.gov, last updated 2026-11-09.
Sponsored by Bursa City Hospital · Not applicable, Interventional, and Other
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.
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.
5,640 studies on the registry are indexed under Pain, Postoperative; 1,230 are open to participants now.
This study's planned enrollment of 120 is above the median of 75 across 4,821 interventional studies indexed under Pain, Postoperative.
Browse Pain, Postoperative studies →Bursa City Hospital is the lead sponsor of 71 studies on the registry; 31 are open to participants now.
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Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
The anaesthetists’ scale of health before surgery: I is healthy, II has a mild illness that is under control, III a severe one, IV a severe illness that is a constant threat to life. V and VI are used for the critically ill and for organ donors.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
ASA physical status
The anaesthetists’ scale of health before surgery: I is healthy, II has a mild illness that is under control, III a severe one, IV a severe illness that is a constant threat to life. V and VI are used for the critically ill and for organ donors.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
BMI (body mass index)
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraindication
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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.
Other: Proximal Adductor Canal Block
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.
Other: Mid Adductor Canal Block
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.
Other: Distal Adductor Canal Block
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.
Ultrasound-guided in-plane injection at the classic mid-thigh level, where the femoral artery lies beneath the sartorius muscle.
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.
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.
Time frame: Postoperative 0-24 hours
Pain Scores at Rest
Pain at rest assessed with the Numeric Rating Scale (NRS; 0 = no pain, 10 = worst imaginable pain).
Time frame: 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).
Time frame: 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.
Time frame: 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.
Time frame: Postoperative 0-48 hours
No study locations are listed for this record.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
This study is not yet recruiting, as verified in Nov 2026. You cannot join it, but the record below documents what was studied.
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Bursa City Hospital