Postoperative Pain After Total Knee ArthroplastyNCT07588958
Genicular Nerve Versus Adductor Canal Block for Postoperative Analgesia
A study testing Spinal Anesthesia with Bupivacaine and Fentanyl, Genicular nerve block with bupivacaine and Adductor Canal Block (ACB) Only in people with Postoperative Pain After Total Knee Arthroplasty, run by Zagazig University at 1 site in Egypt.
Trial summary
Severe postoperative pain following total knee arthroplasty (TKA ) has been shown to negatively affect early mobilization, physical rehabilitation, time to discharge, and overall post-operative recovery.Therefore, reducing postoperative pain and early mobilization has become critical in reducing early mortality… Read more about this study
- Who is it for?
- Ages 65 years and older
- Conditions the study is for
- Postoperative Pain After Total Knee Arthroplasty
- What is being tested?
- Spinal Anesthesia with Bupivacaine and Fentanyl, Genicular nerve block with bupivacaine and Adductor Canal Block (ACB) Only
- Type of treatment
- Injection or infusion
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 42 participants
- Where
- 1 siteEgypt
- Study dates
- 1 Oct 2023to 19 Jun 2026
- 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 65 years and older
- All sexes
- No healthy volunteers
- Older adult
Who may be able to join
- Patient acceptance.
- Sex: both; male and female.
- Age: over 65 years old.
- American society of anesthesiologists (ASA): II .
- Body mass index (BMI) less than 35 kg/m2.
- Operation : elective unilateral TKA.
- Duration of surgery : 2-3 hours.
Who cannot join
- History of allergy to local anesthetics (lidocaine or bupivicaine).
- Coexisting hematologic disorders or malnourished patient.
- Pre-existing major organ dysfunction including hepatic or renal failure, and left ventricular ejection fraction <30%
- Peripheral neuropathy.
- Patients with a diagnosis of cognitive impairment or significant psychiatric illness.
- Skin infection at site of block.
- Contraindication to spinal anesthesia as coagulopathy and infection at site of injection.
Trial locations and contacts
1 site in 1 country.
About this study
Official title: Genicular Nerve Versus Adductor Canal Block for Postoperative Analgesia in Patients Undergoing Total Knee Arthroplasty
Severe postoperative pain following total knee arthroplasty (TKA ) has been shown to negatively affect early mobilization, physical rehabilitation, time to discharge, and overall post-operative recovery.Therefore, reducing postoperative pain and early mobilization has become critical in reducing early mortality, preventing future chronic pain, and limiting the use of opioids The adductor canal block (ACB) has been found to be an excellent alternative to the FNB, providing adequate analgesia to the anterior knee compartment while enabling an improved postoperative range of motion by sparing motor branches to the quadriceps muscles . However, patients do not achieve adequate posterior knee analgesia as ACB pain relief is primarily limited to the anterior capsule of the knee.
Genicular nerve block (GNB) and radiofrequency ablation of genicular nerves (RFGN) were originally introduced by Choi et al. as a therapeutic alternative for chronic knee OA and were quickly adopted for use in patients undergoing TKA due to the significant pain reduction and functional improvement observed in these patients . GNBs target five main innervating branches of the knee, including the superomedial, inferomedial, superolateral, inferolateral genicular nerves, and the infrapatellar branch of the saphenous nerve.
Read the detailed description
Chronic knee osteoarthritis (OA), an epidemic among aging populations, is a leading source of chronic pain in the United States and other developed countries . The rise in prevalence of knee OA is a direct result of factors including longer life expectancy and increased body mass index (BMI). It has been reported that at least 19% of American adults aged 45 years and older are affected . Severe postoperative pain following total knee arthroplasty (TKA ) has been shown to negatively affect early mobilization, physical rehabilitation, time to discharge, and overall post-op recovery
.Therefore, reducing postoperative pain and early mobilization has become critical in reducing early mortality, preventing future chronic pain, and limiting the use of opioids . Balancing pain control with patient ambulation often proves to be a challenge due to both the motor blocking effects of many proximal nerve blocks and the often inadequate analgesia associated with more superficial periarticular injections . Therefore, numerous modalities of analgesic treatment combining different methods of nerve blockade for effective postoperative analgesia and faster functional recovery have been discussed . However, the superior technique is yet to be
determined. Successful postoperative analgesia for TKA requires careful consideration of knee innervation, with an emphasis placed on branches of the femoral nerve innervating the anterior and medical aspects of the knee and branches of the sciatic nerve innervating the posterior aspects of the knee capsule . In the context of nerve blockade, femoral nerve block (FNB) has traditionally been a critical component in the multimodal management of pain in TKA patients due to the high analgesic efficacy and the minimal risks associated. However, FNB is associated with decreased quadriceps motor strength leading to limited physical therapy (PT) participation, delayed ambulation, and discharge . The adductor canal block (ACB) has been found to be an excellent alternative to the FNB, providing adequate analgesia to the anterior knee compartment while enabling an improved postoperative range of motion by sparing motor branches to the quadriceps muscles . However, patients do not achieve adequate posterior knee analgesia as ACB pain relief is primarily limited to the anterior capsule of the knee.
Genicular nerve block (GNB) and radiofrequency ablation of genicular nerves (RFGN) were originally introduced by Choi et al. as a therapeutic alternative for chronic knee OA and were quickly adopted for use in patients undergoing TKA due to the significant pain reduction and functional improvement observed in these patients . GNBs target five main innervating branches of the knee, including the superomedial, inferomedial, superolateral, inferolateral genicular nerves, and the infrapatellar branch of the saphenous nerve. Several bony landmarks surrounding these nerves aid in proper needle placement under fluoroscopic guidance . The GNB has a motor-sparing effect that is desirable for early ambulation postoperatively, better PT, and earlier discharge .
- Being tested
- Spinal Anesthesia with Bupivacaine and Fentanyl, Genicular nerve block with bupivacaine, Adductor Canal Block (ACB) Only
- Keywords
- genicular nerve block, Adductor canal block, postoperative analgesia, total knee arthroplasty
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Spinal Anesthesia with Bupivacaine and FentanylOther
spinal anesthesia will be given (under complete aseptic conditions) at the level of L3/4 while the patient in the sitting position using a spinal needle 25 G x 3.5 inches with injection of hyperbaric bupivacaine 0.5% 3ml plus fentanyl 25 microgram .
Genicular nerve block with bupivacaineOther
For the superomedial genicular nerve, a linear transducer will be placed along the longitudinal plane of the femur to visualize vastus medialis, the distal femur, and the genicular artery. Using an in-plane technique, a 10-cm echogenic 21-gauge needle will be advanced in the cephalad to the caudad direction until the needle contacted femoral shaft, just cephalad to the genicular artery, and 5 ml of 0.25% bupivacaine will be injected to spread along the femoral periosteum. This same technique, using 5 ml of 0.25% bupivacaine, will be used in a mirror image on the lateral epicondyle to block the superolateral genicular nerve.
To target the inferomedial genicular nerve, a linear transducer will be placed in the sagittal plane on the anterior medial tibia.
Adductor Canal Block (ACB) OnlyOther
The transducer will be placed anteromedially midway between inguinal crease and medial condyle to identify sartorius muscle. Probe will be positioned perpendicular to the femoral artery and using in-plane technique with needle directed from lateral to medial to deposit local anesthetic under sartorius and around the femoral artery. 15ml bupivacaine 0.25% will be injected
| Study group | Role | What they receive |
|---|---|---|
| control group | Other | Receive spinal anesthesia Receives: Other: Spinal Anesthesia with Bupivacaine and Fentanyl |
| Genicular nerve block group | Active comparator | Receive Genicular Nerve Block Receives: Other: Genicular nerve block with bupivacaine |
| Adductor canal block group | Active comparator | Receive Adductor canal block Receives: Other: Adductor Canal Block (ACB) Only |
What is being measured
The primary outcome is the main question the study is designed to answer.
changes of pain assessment
visual analogue scale
Measured: time frame ( at PACU, 2 hours (h ) , 4 , 8 , 12 , 16 , 24 hours postoperatively )
Secondary outcomes (1)
Modified Bromage scale
no motor nerveblock in the lower extremity = 0 point; the affected limb cannot lift the leg = 1 point; failure to bend the knee of the affected limb = 2 points; and failure to bend the ankle = 3points
Measured: at PACU, 3 hours and 6 hours postoperatively
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted15 May 2026
- Study start1 Oct 2023
- Primary completion6 May 2026 (estimated)
- Study completion19 Jun 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Postoperative 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
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Prevention
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Double blind
- Who is masked
- Participant, Outcomes assessor
- Enrolment
- 42 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Zagazig University
- Sponsor type
- Other government
- Responsible party
- Principal investigator, Soha Saad Eldin Mohamed Hassouna, Zagazig University
- Investigators
- Soha Saad mohamed Hassouna, PHD, Principal investigator, Faculty of medicine - zagazig university
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07588958
- Sponsor's protocol ID
- 10793-14/5-2023
- Status last verified
- May 2026
- First submitted
- 9 May 2026
- Last updated
- 15 May 2026
- Results posted
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Yes: Planned after completion of the study and publications
Study at a glance
From the registry record, last updated by the sponsor on 15 May 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Genicular Nerve Versus Adductor Canal Block for Postoperative Analgesia in Patients Undergoing Total Knee Arthroplasty
- ClinicalTrials.gov ID
- NCT07588958
- Acronym / sponsor ID
- 10793-14/5-2023
- Keywords
- genicular nerve block, Adductor canal block, postoperative analgesia, total knee arthroplasty
- Study type
- Interventional
- Recruitment status
- Active, not recruiting
- Enrolment
- 42 participants (estimated)
- Lead sponsor
- Zagazig UniversityOther government
- Study start
- 1 Oct 2023 (actual)
- Primary completion
- 6 May 2026 (estimated)
- Study completion
- 19 Jun 2026 (estimated)
- First posted
- 15 May 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.
Severe postoperative pain following total knee arthroplasty (TKA ) has been shown to negatively affect early mobilization, physical rehabilitation, time to discharge, and overall post-operative recovery.Therefore, reducing postoperative pain and early mobilization has become critical in reducing early mortality, preventing future chronic pain, and limiting the use of opioids The adductor canal block (ACB) has been found to be an excellent alternative to the FNB, providing adequate analgesia to the anterior knee compartment while enabling an improved postoperative range of motion by sparing motor branches to the quadriceps muscles . However, patients do not achieve adequate posterior knee analgesia as ACB pain relief is primarily limited to the anterior capsule of the knee.
Genicular nerve block (GNB) and radiofrequency ablation of genicular nerves (RFGN) were originally introduced by Choi et al. as a therapeutic alternative for chronic knee OA and were quickly adopted for use in patients undergoing TKA due to the significant pain reduction and functional improvement observed in these patients . GNBs target five main innervating branches of the knee, including the superomedial, inferomedial, superolateral, inferolateral genicular nerves, and the infrapatellar branch of the saphenous nerve.
Detailed description
Chronic knee osteoarthritis (OA), an epidemic among aging populations, is a leading source of chronic pain in the United States and other developed countries . The rise in prevalence of knee OA is a direct result of factors including longer life expectancy and increased body mass index (BMI). It has been reported that at least 19% of American adults aged 45 years and older are affected . Severe postoperative pain following total knee arthroplasty (TKA ) has been shown to negatively affect early mobilization, physical rehabilitation, time to discharge, and overall post-op recovery
.Therefore, reducing postoperative pain and early mobilization has become critical in reducing early mortality, preventing future chronic pain, and limiting the use of opioids . Balancing pain control with patient ambulation often proves to be a challenge due to both the motor blocking effects of many proximal nerve blocks and the often inadequate analgesia associated with more superficial periarticular injections . Therefore, numerous modalities of analgesic treatment combining different methods of nerve blockade for effective postoperative analgesia and faster functional recovery have been discussed . However, the superior technique is yet to be
determined. Successful postoperative analgesia for TKA requires careful consideration of knee innervation, with an emphasis placed on branches of the femoral nerve innervating the anterior and medical aspects of the knee and branches of the sciatic nerve innervating the posterior aspects of the knee capsule . In the context of nerve blockade, femoral nerve block (FNB) has traditionally been a critical component in the multimodal management of pain in TKA patients due to the high analgesic efficacy and the minimal risks associated. However, FNB is associated with decreased quadriceps motor strength leading to limited physical therapy (PT) participation, delayed ambulation, and discharge . The adductor canal block (ACB) has been found to be an excellent alternative to the FNB, providing adequate analgesia to the anterior knee compartment while enabling an improved postoperative range of motion by sparing motor branches to the quadriceps muscles . However, patients do not achieve adequate posterior knee analgesia as ACB pain relief is primarily limited to the anterior capsule of the knee.
Genicular nerve block (GNB) and radiofrequency ablation of genicular nerves (RFGN) were originally introduced by Choi et al. as a therapeutic alternative for chronic knee OA and were quickly adopted for use in patients undergoing TKA due to the significant pain reduction and functional improvement observed in these patients . GNBs target five main innervating branches of the knee, including the superomedial, inferomedial, superolateral, inferolateral genicular nerves, and the infrapatellar branch of the saphenous nerve. Several bony landmarks surrounding these nerves aid in proper needle placement under fluoroscopic guidance . The GNB has a motor-sparing effect that is desirable for early ambulation postoperatively, better PT, and earlier discharge .
Study design
- Primary purpose
- Prevention
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Double blind (participant, outcomes assessor)
- Number of arms
- 3
| Arm | Type | Receives |
|---|---|---|
| control group | Other | Other: Spinal Anesthesia with Bupivacaine and FentanylReceive spinal anesthesia |
| Genicular nerve block group | Active comparator | Other: Genicular nerve block with bupivacaineReceive Genicular Nerve Block |
| Adductor canal block group | Active comparator | Other: Adductor Canal Block (ACB) OnlyReceive Adductor canal block |
Who may qualify
- Ages
- 65 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Older adult
Key inclusion criteria (7 listed)
- Patient acceptance.
- Sex: both; male and female.
- Age: over 65 years old.
- American society of anesthesiologists (ASA): II .
- Body mass index (BMI) less than 35 kg/m2.
Key exclusion criteria (7 listed)
- History of allergy to local anesthetics (lidocaine or bupivicaine).
- Coexisting hematologic disorders or malnourished patient.
- Pre-existing major organ dysfunction including hepatic or renal failure, and left ventricular ejection fraction <30%
- Peripheral neuropathy.
- Patients with a diagnosis of cognitive impairment or significant psychiatric illness.
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 |
|---|---|---|
| Spinal Anesthesia with Bupivacaine and Fentanylspinal anesthesia will be given (under complete aseptic conditions) at the level of L3/4 while the patient in the sitting position using a spinal needle 25 G x 3.5 inches with injection of hyperbaric bupivacaine 0.5% 3ml plus fentanyl 25 microgram . | Other | control group |
| Genicular nerve block with bupivacaineFor the superomedial genicular nerve, a linear transducer will be placed along the longitudinal plane of the femur to visualize vastus medialis, the distal femur, and the genicular artery. Using an in-plane technique, a 10-cm echogenic 21-gauge needle will be advanced in the cephalad to the caudad direction until the needle contacted femoral shaft, just cephalad to the genicular artery, and 5 ml of 0.25% bupivacaine will be injected to spread along the femoral periosteum. This same technique, using 5 ml of 0.25% bupivacaine, will be used in a mirror image on the lateral epicondyle to block the superolateral genicular nerve. To target the inferomedial genicular nerve, a linear transducer will be placed in the sagittal plane on the anterior medial tibia. | Other | Genicular nerve block group |
| Adductor Canal Block (ACB) OnlyThe transducer will be placed anteromedially midway between inguinal crease and medial condyle to identify sartorius muscle. Probe will be positioned perpendicular to the femoral artery and using in-plane technique with needle directed from lateral to medial to deposit local anesthetic under sartorius and around the femoral artery. 15ml bupivacaine 0.25% will be injected | Other | Adductor canal block group |
Primary outcome
changes of pain assessment
Time frame: time frame ( at PACU, 2 hours (h ) , 4 , 8 , 12 , 16 , 24 hours postoperatively )
visual analogue scale
1 secondary outcome
Modified Bromage scale
Time frame: at PACU, 3 hours and 6 hours postoperatively
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 15 May 2026.
- Individual participant dataSharing planned: Yes. Planned after completion of the study and publications
Related trials for Postoperative Pain After Total Knee Arthroplasty
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Oral Tranexamic Acid After Total Knee Arthroplasty
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A Randomized Comparison of the Efficacy of the IPACK Block Versus the Popliteal Plexus Block for Posterior Knee Analgesia, in Patients Undergoing a Total Knee Arthroplasty and Receiving a Continuous Distal Femoral Triangle Block
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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.
Soha Saad mohamed Hassouna, PHD principal investigator
Faculty of medicine - zagazig university
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Spinal Anesthesia with Bupivacaine and Fentanyl, Genicular nerve block with bupivacaine and Adductor Canal Block (ACB) Only in people with Postoperative Pain After Total Knee Arthroplasty, run by Zagazig University at 1 site in Egypt.
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 7 inclusion and 7 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: under way, not looking for participants, as of the sponsor's last update on 15 May 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 Egypt. 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?
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?
changes of pain assessment (time frame: time frame ( at PACU, 2 hours (h ) , 4 , 8 , 12 , 16 , 24 hours postoperatively )). 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 15 May 2026.