Knee Stiffness After Total Knee ArthroplastyPhase 4NCT07348614
Flex Appeal: Evaluating the Efficacy of Anesthetic Techniques for Manipulation of Knees Under Anesthesia
A Phase 4 study testing Spinal Anesthesia, General Anesthesia and Propofol in people with Knee Stiffness After Total Knee Arthroplasty, run by Duke University at 1 site in United States.
Trial summary
The purpose of this study is to determine if changing the type of anesthesia improves the outcomes of manipulation and pain control after the procedure. The study will compare a spinal anesthesia with a general anesthesia, to see if there is a better outcome from either anesthesia type. Read more about this study
- Who is it for?
- Ages 18 to 75 years
- Conditions the study is for
- Knee Stiffness After Total Knee Arthroplasty
- What is being tested?
- Spinal Anesthesia, General Anesthesia and Propofol
- Type of treatment
- Injection or infusion, Surgery or procedure
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 128 participants
- Where
- 1 siteUnited States
- Study dates
- 1 Jun 2026to Sep 2027
- Phase
- Phase 4
- 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
- Patients ≥18 years presenting for a manipulation of knee joint under anesthesia.
- ASA Classification I - III.
- English speaking patients.
Who cannot join
- ASA 4 or 5
- Daily chronic opioid use (over 3 months of continuous opioid use).
- Inability to communicate pain scores or need for analgesia.
- Infection at the site of block placement
- Age under 18 years old or greater than 75 years old
- Pregnant women (as determined by point-of-care serum bHCG)
Show all 15Show fewer
- Intolerance/allergy to local anesthetics
- Weight <50 kg
- Suspected, or known addiction to or abuse of illicit drug(s), prescription medicine(s), or alcohol within the past 2 years.
- Uncontrolled anxiety, schizophrenia, or other psychiatric disorder that, in the opinion of the investigator, may interfere with study assessments or compliance.
- Current or historical evidence of any clinically significant disease or condition that, in the opinion of the investigator, may increase the risk of surgery or complicate the subject's postoperative course.
- BMI >50 kg/m2.
- Allergy or contraindication to local anesthetics or any component of the multimodal analgesic regimen
- (NSAIDs and acetaminophen)
- Contraindication to spinal injection
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
United States1 site, 1 recruiting
- Recruiting
Duke University Health System
Durham, North Carolina, 27705
Emily Hall, MD, 919-681-0880, ezb2@duke.edu
Emily Hall, MD
About this study
Official title: Flex Appeal: A Prospective Randomized Controlled Trial Evaluating the Efficacy of Anesthetic Techniques for Manipulation of Knees Under Anesthesia (MUA)
The purpose of this study is to determine if changing the type of anesthesia improves the outcomes of manipulation and pain control after the procedure. The study will compare a spinal anesthesia with a general anesthesia, to see if there is a better outcome from either anesthesia type.
- Being tested
- Spinal Anesthesia, General Anesthesia, Propofol, Chloroprocaine
- Keywords
- knee arthroplasty, spinal anesthesia, general anesthesia
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Spinal AnesthesiaProcedure or surgery
Administration of spinal anesthesia for knee manipulation.
General AnesthesiaProcedure or surgery
Administration of general anesthesia for knee manipulation.
PropofolDrug
Patients undergoing general anesthesia will receive an induction dose of propofol that will be titrated to effect, and airway support as needed until the patient is appropriately anesthetized for the procedure as determined by the anesthesia and surgical care teams.
ChloroprocaineDrug
Patients undergoing spinal anesthesia will receive a spinal injection under standard aseptic technique, with 45mg chloroprocaine.
| Study group | Role | What they receive |
|---|---|---|
| Spinal Anesthesia | Experimental | Patients receive spinal anesthesia during MUA (manipulation under anesthesia). Receives: Procedure: Spinal Anesthesia; Drug: Chloroprocaine |
| General Anesthesia | Active comparator | Patients receive general anesthesia during MUA (manipulation under anesthesia). Receives: Procedure: General Anesthesia; Drug: Propofol |
What is being measured
The primary outcome is the main question the study is designed to answer.
Change in degrees of motion of the affected knee
Measured: At time of procedure completion
Secondary outcomes (2)
Change in pain
Participants will be asked to rate pain on a scale of 0-10 with 0 being no pain and 10 being the worst possible pain.
Measured: Baseline, 24 hours, 48 hours, 72 hours post-procedure
Opioid use in PACU
Measured: Day 3
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted16 Jan 2026
- Study start1 Jun 2026
- Primary completionAug 2027 (estimated)
- Study completionSep 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Knee Stiffness After Total Knee ArthroplastyStudies of the same condition, open and under way.
- More trials run by Duke UniversityThe sponsor's other registered studies.
- 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 4
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Single blind
- Who is masked
- Outcomes assessor
- Enrolment
- 128 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Duke University
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
- Investigators
- Emily Hall, Principal investigator, Duke University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07348614
- Sponsor's protocol ID
- Pro00118605
- Status last verified
- Jan 2026
- First submitted
- 14 Jan 2026
- Last updated
- 3 Jun 2026
- Results posted
- No
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 3 Jun 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Flex Appeal: A Prospective Randomized Controlled Trial Evaluating the Efficacy of Anesthetic Techniques for Manipulation of Knees Under Anesthesia (MUA)
- ClinicalTrials.gov ID
- NCT07348614
- Acronym / sponsor ID
- Pro00118605
- Keywords
- knee arthroplasty, spinal anesthesia, general anesthesia
- Phase
- Phase 4
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 128 participants (estimated)
- Lead sponsor
- Duke UniversityUniversity, hospital or other
- Study start
- 1 Jun 2026 (actual)
- Primary completion
- Aug 2027 (estimated)
- Study completion
- Sep 2027 (estimated)
- First posted
- 16 Jan 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 purpose of this study is to determine if changing the type of anesthesia improves the outcomes of manipulation and pain control after the procedure. The study will compare a spinal anesthesia with a general anesthesia, to see if there is a better outcome from either anesthesia type.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Single blind (outcomes assessor)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Spinal Anesthesia | Experimental | Procedure: Spinal Anesthesia, Drug: ChloroprocainePatients receive spinal anesthesia during MUA (manipulation under anesthesia). |
| General Anesthesia | Active comparator | Procedure: General Anesthesia, Drug: PropofolPatients receive general anesthesia during MUA (manipulation under anesthesia). |
Who may qualify
- Ages
- 18 to 75 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (3 listed)
- Patients ≥18 years presenting for a manipulation of knee joint under anesthesia.
- ASA Classification I - III.
- English speaking patients.
Key exclusion criteria (15 listed)
- ASA 4 or 5
- Daily chronic opioid use (over 3 months of continuous opioid use).
- Inability to communicate pain scores or need for analgesia.
- Infection at the site of block placement
- Age under 18 years old or greater than 75 years old
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 AnesthesiaAdministration of spinal anesthesia for knee manipulation. | Procedure or surgery | Spinal Anesthesia |
| General AnesthesiaAdministration of general anesthesia for knee manipulation. | Procedure or surgery | General Anesthesia |
| PropofolPatients undergoing general anesthesia will receive an induction dose of propofol that will be titrated to effect, and airway support as needed until the patient is appropriately anesthetized for the procedure as determined by the anesthesia and surgical care teams. | Drug | General Anesthesia |
| ChloroprocainePatients undergoing spinal anesthesia will receive a spinal injection under standard aseptic technique, with 45mg chloroprocaine. | Drug | Spinal Anesthesia |
Primary outcome
Change in degrees of motion of the affected knee
Time frame: At time of procedure completion
2 secondary outcomes
Change in pain
Time frame: Baseline, 24 hours, 48 hours, 72 hours post-procedure
Opioid use in PACU
Time frame: Day 3
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 3 Jun 2026.
- Individual participant dataSharing planned: No
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.
Emily Hall principal investigator
Duke University
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 4 study testing Spinal Anesthesia, General Anesthesia and Propofol in people with Knee Stiffness After Total Knee Arthroplasty, run by Duke University at 1 site in United States.
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 3 inclusion and 15 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: looking for participants now, as of the sponsor's last update on 3 Jun 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 United States. 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.
What does this phase mean?
Phase 4 studies take place after a treatment is approved, to learn more about its long-term benefits and risks in everyday use.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
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?
Each site lists its own contact: choose the nearest one under Trial locations. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Change in degrees of motion of the affected knee (time frame: At time of procedure completion). 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 Jun 2026; AzTrials last refreshed its copy on 6 Nov 2026.