Postoperative Pain After Total Knee ArthroplastyNCT07891221
Agreement Between Patient-Reported Pain, Observer-Rated Pain Behavior, and Analgesic Request After Total Knee Arthroplasty
An observational study of Postoperative Pain After Total Knee Arthroplasty, run by Gamze Kübra Zelyurt.
Trial summary
The goal of this observational study is to learn how well patients' own pain ratings match what an observer sees and whether the patient asks for extra pain medicine after total knee replacement surgery. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Postoperative Pain After Total Knee Arthroplasty
- How many people
- 120 participants
- Where
- No sites listed yet
- Study dates
- 1 Nov 2026to 1 May 2027
- How long will I take part?
- 1 Day
- Phase
- Observational
- 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 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Study population: Adult patients (18 years or older) undergoing elective primary total knee arthroplasty under spinal anesthesia at Sincan Training and Research Hospital, Ankara, Turkey. Consecutive eligible patients who provide written informed consent will be enrolled.
Who may be able to join
- Age 18 years or older
- Scheduled for elective primary total knee arthroplasty
- Surgery performed under spinal anesthesia
- Able to undergo postoperative pain assessments
- Written informed consent
Who cannot join
- Cognitive impairment or history of dementia
- Severe hearing or communication impairment
- Chronic opioid use
- Serious psychiatric illness
- Revision knee arthroplasty
- Conversion to general anesthesia
- Refusal to participate
Trial locations and contacts
No sites are listed yet. Contact the study team or a site near you to ask about taking part.
About this study
Official title: Agreement Between Patient-Reported Pain Intensity, Observer-Rated Pain Behavior, and Analgesic Request in Postoperative Pain Assessment After Total Knee Arthroplasty: A Prospective Observational Study
The goal of this observational study is to learn how well patients' own pain ratings match what an observer sees and whether the patient asks for extra pain medicine after total knee replacement surgery. The study will include adults aged 18 years or older having planned (elective) total knee replacement under spinal anesthesia.
The main questions it aims to answer are:
Read more
- Does the pain score reported by the patient (Numeric Rating Scale, 0-10) agree with the patient's request for additional pain medicine?
- Does the pain score reported by the patient agree with pain behavior rated by an observer (facial expression, body movements, and vocal expressions)?
No treatment will be changed for this study. All patients will receive the hospital's standard anesthesia and pain management.
Participants will:
- Rate their pain from 0 (no pain) to 10 (worst pain imaginable) at 2, 6, and 24 hours after surgery
- Be observed by a researcher who scores their pain behavior at the same time points
- Be asked whether they would like additional pain medicine at each time point
Read the detailed description
Postoperative pain is a major determinant of recovery after total knee arthroplasty (TKA), affecting patient satisfaction, early mobilization, and rehabilitation. The Numeric Rating Scale (NRS) is among the most widely used tools for postoperative pain assessment and frequently guides analgesic decisions. However, pain is a subjective and multidimensional experience, and patients with similar NRS scores may display different levels of pain behavior and analgesic need. Although patient-reported pain intensity, observed pain behavior, and analgesic request have each been studied, few studies have evaluated these three components simultaneously in the early postoperative period.
This single-center, prospective observational study will be conducted at Sincan Training and Research Hospital, Ankara, Turkey. No intervention, randomization, or change in anesthesia or analgesia protocol will be made; all procedures follow routine clinical practice. Written informed consent will be obtained preoperatively.
Adult patients (18 years or older, ASA physical status I-III) undergoing elective primary TKA under spinal anesthesia will be included. Demographic data (age, sex, height, weight), ASA physical status, comorbidities, and perioperative clinical data will be recorded on standardized case report forms.
At postoperative hours 2, 6, and 24:
- Patient-reported pain intensity will be assessed with the NRS (0 = no pain, 10 = worst pain imaginable).
- Observer-rated pain behavior will be scored with a standardized behavioral pain assessment developed by the investigators, adapted from established behavioral scales (CPOT, FLACC). Facial expression, body movements, and vocal expressions are each scored 0-2 (total score 0-6; higher scores indicate more pronounced pain behavior).
- Patients will be asked whether they feel the need for additional analgesia (analgesic request: yes/no).
All patients will receive the institution's standard postoperative multimodal analgesia protocol. Routine analgesics, rescue analgesic administrations, their timing, and total analgesic consumption over the first 24 postoperative hours will be recorded.
Sample size: Based on a power of 90% and a type I error of 5% (G*Power 3.1), assuming a medium effect size, a minimum of 112 patients is required. Allowing for data loss and incomplete records, at least 120 patients will be enrolled.
Statistical analysis: Analyses will be performed with IBM SPSS Statistics. Relationships between NRS, observer-rated pain behavior score, and analgesic request will be analyzed using appropriate parametric or non-parametric tests, including Pearson or Spearman correlation, and chi-square or Fisher's exact test. A p value < 0.05 will be considered statistically significant.
The findings are expected to clarify the clinical validity of numeric pain scores and support a more comprehensive approach to postoperative pain assessment and analgesic decision-making.
- Keywords
- Numeric Rating Scale, Total Knee Arthroplasty, Pain Measurement, Behavioral Pain Assessment, Analgesic Request
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 |
|---|---|---|
| Total Knee Arthroplasty Patients | Adult patients (18 years or older, ASA I-III) undergoing elective primary total knee arthroplasty under spinal anesthesia. Patient-reported pain (NRS), observer-rated pain behavior, and analgesic request will be assessed at postoperative 2, 6, and 24 hours. No study intervention is applied; all patients receive standard institutional anesthesia and analgesia care. |
What is being measured
The primary outcome is the main question the study is designed to answer.
Agreement Between Patient-Reported Pain Intensity (NRS) and Observer-Rated Pain Behavior Score
Observer-rated pain behavior is scored with a standardized behavioral pain assessment adapted from CPOT and FLACC: facial expression, body movements, and vocal expressions, each scored 0-2 (total 0-6; higher scores indicate more pronounced pain behavior). Correlation/agreement with simultaneous NRS scores will be analyzed.
Measured: Postoperative 2, 6, and 24 hours
Secondary outcomes (1)
Association Between Patient-Reported Pain Intensity (NRS) and Analgesic Request
Patients rate their current pain on the Numeric Rating Scale (NRS; 0 = no pain, 10 = worst pain imaginable) and are asked whether they need additional analgesia (yes/no) at each time point. The association/agreement between NRS scores and analgesic request will be analyzed (e.g., point-biserial/Spearman correlation and comparison of NRS scores between patients who do and do not request analgesia).
Measured: Postoperative 2, 6, and 24 hours
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted23 Oct 2026
- Study start1 Nov 2026 (estimated)
- Primary completion1 Feb 2027 (estimated)
- Study completion1 May 2027 (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
- Observational
- Observational model
- Cohort
- Time perspective
- Prospective
- Enrolment
- 120 participants (estimated)
- Target duration
- 1 Day
Sponsor and investigators
- Lead sponsor
- Gamze Kübra Zelyurt
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor-investigator, Gamze Kübra Zelyurt, Sincan Training and Research Hospital
- Investigators
- Nagihan Emiroglu, Principal investigator, Sincan Training and Research
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07891221
- Sponsor's protocol ID
- SEAH-BAEK-2026-276
- Status last verified
- Oct 2026
- First submitted
- 15 Oct 2026
- Last updated
- 23 Oct 2026
- Results posted
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No: Individual participant data will not be shared publicly, in accordance with the ethics committee approval and the informed consent, which ensure participant confidentiality. Aggregated results will be published in a peer-reviewed journal.
Study at a glance
From the registry record, last updated by the sponsor on 23 Oct 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Agreement Between Patient-Reported Pain Intensity, Observer-Rated Pain Behavior, and Analgesic Request in Postoperative Pain Assessment After Total Knee Arthroplasty: A Prospective Observational Study
- ClinicalTrials.gov ID
- NCT07891221
- Acronym / sponsor ID
- SEAH-BAEK-2026-276
- Keywords
- Numeric Rating Scale, Total Knee Arthroplasty, Pain Measurement, Behavioral Pain Assessment, Analgesic Request
- Study type
- Observational
- Recruitment status
- Not yet recruiting
- Enrolment
- 120 participants (estimated)
- Lead sponsor
- Gamze Kübra ZelyurtUniversity, hospital or other
- Study start
- 1 Nov 2026 (estimated)
- Primary completion
- 1 Feb 2027 (estimated)
- Study completion
- 1 May 2027 (estimated)
- First posted
- 23 Oct 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 observational study is to learn how well patients' own pain ratings match what an observer sees and whether the patient asks for extra pain medicine after total knee replacement surgery. The study will include adults aged 18 years or older having planned (elective) total knee replacement under spinal anesthesia.
The main questions it aims to answer are:
- Does the pain score reported by the patient (Numeric Rating Scale, 0-10) agree with the patient's request for additional pain medicine?
- Does the pain score reported by the patient agree with pain behavior rated by an observer (facial expression, body movements, and vocal expressions)?
No treatment will be changed for this study. All patients will receive the hospital's standard anesthesia and pain management.
Participants will:
- Rate their pain from 0 (no pain) to 10 (worst pain imaginable) at 2, 6, and 24 hours after surgery
- Be observed by a researcher who scores their pain behavior at the same time points
- Be asked whether they would like additional pain medicine at each time point
Detailed description
Postoperative pain is a major determinant of recovery after total knee arthroplasty (TKA), affecting patient satisfaction, early mobilization, and rehabilitation. The Numeric Rating Scale (NRS) is among the most widely used tools for postoperative pain assessment and frequently guides analgesic decisions. However, pain is a subjective and multidimensional experience, and patients with similar NRS scores may display different levels of pain behavior and analgesic need. Although patient-reported pain intensity, observed pain behavior, and analgesic request have each been studied, few studies have evaluated these three components simultaneously in the early postoperative period.
This single-center, prospective observational study will be conducted at Sincan Training and Research Hospital, Ankara, Turkey. No intervention, randomization, or change in anesthesia or analgesia protocol will be made; all procedures follow routine clinical practice. Written informed consent will be obtained preoperatively.
Adult patients (18 years or older, ASA physical status I-III) undergoing elective primary TKA under spinal anesthesia will be included. Demographic data (age, sex, height, weight), ASA physical status, comorbidities, and perioperative clinical data will be recorded on standardized case report forms.
At postoperative hours 2, 6, and 24:
- Patient-reported pain intensity will be assessed with the NRS (0 = no pain, 10 = worst pain imaginable).
- Observer-rated pain behavior will be scored with a standardized behavioral pain assessment developed by the investigators, adapted from established behavioral scales (CPOT, FLACC). Facial expression, body movements, and vocal expressions are each scored 0-2 (total score 0-6; higher scores indicate more pronounced pain behavior).
- Patients will be asked whether they feel the need for additional analgesia (analgesic request: yes/no).
All patients will receive the institution's standard postoperative multimodal analgesia protocol. Routine analgesics, rescue analgesic administrations, their timing, and total analgesic consumption over the first 24 postoperative hours will be recorded.
Sample size: Based on a power of 90% and a type I error of 5% (G*Power 3.1), assuming a medium effect size, a minimum of 112 patients is required. Allowing for data loss and incomplete records, at least 120 patients will be enrolled.
Statistical analysis: Analyses will be performed with IBM SPSS Statistics. Relationships between NRS, observer-rated pain behavior score, and analgesic request will be analyzed using appropriate parametric or non-parametric tests, including Pearson or Spearman correlation, and chi-square or Fisher's exact test. A p value < 0.05 will be considered statistically significant.
The findings are expected to clarify the clinical validity of numeric pain scores and support a more comprehensive approach to postoperative pain assessment and analgesic decision-making.
Study design
- Observational model
- Cohort
- Time perspective
- Prospective
- Target follow-up
- 1 Day
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| Total Knee Arthroplasty Patients | – | –Adult patients (18 years or older, ASA I-III) undergoing elective primary total knee arthroplasty under spinal anesthesia. Patient-reported pain (NRS), observer-rated pain behavior, and analgesic request will be assessed at postoperative 2, 6, and 24 hours. No study intervention is applied; all patients receive standard institutional anesthesia and analgesia care. |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
- Study population
- Adult patients (18 years or older) undergoing elective primary total knee arthroplasty under spinal anesthesia at Sincan Training and Research Hospital, Ankara, Turkey. Consecutive eligible patients who provide written informed consent will be enrolled.
Key inclusion criteria (5 listed)
- Age 18 years or older
- Scheduled for elective primary total knee arthroplasty
- Surgery performed under spinal anesthesia
- Able to undergo postoperative pain assessments
- Written informed consent
Key exclusion criteria (7 listed)
- Cognitive impairment or history of dementia
- Severe hearing or communication impairment
- Chronic opioid use
- Serious psychiatric illness
- Revision knee arthroplasty
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
Agreement Between Patient-Reported Pain Intensity (NRS) and Observer-Rated Pain Behavior Score
Time frame: Postoperative 2, 6, and 24 hours
Observer-rated pain behavior is scored with a standardized behavioral pain assessment adapted from CPOT and FLACC: facial expression, body movements, and vocal expressions, each scored 0-2 (total 0-6; higher scores indicate more pronounced pain behavior). Correlation/agreement with simultaneous NRS scores will be analyzed.
1 secondary outcome
Association Between Patient-Reported Pain Intensity (NRS) and Analgesic Request
Time frame: Postoperative 2, 6, and 24 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 23 Oct 2026.
- Individual participant dataSharing planned: No. Individual participant data will not be shared publicly, in accordance with the ethics committee approval and the informed consent, which ensure participant confidentiality. Aggregated results will be published in a peer-reviewed journal.
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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.
Nagihan Emiroglu principal investigator
Sincan Training and Research
Questions about this trial
What is this clinical trial studying?
An observational study of Postoperative Pain After Total Knee Arthroplasty, run by Gamze Kübra Zelyurt.
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 5 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: opening soon, as of the sponsor's last update on 23 Oct 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?
Contact Nagihan Emiroglu, Doctor (+905348167688, nagihanyildiz611@gmail.com), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Agreement Between Patient-Reported Pain Intensity (NRS) and Observer-Rated Pain Behavior Score (time frame: Postoperative 2, 6, and 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 23 Oct 2026.