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Knee Arthroplasty Activity Trial
NCT04107649 · View on ClinicalTrials.gov ↗
Study Summary
Total knee replacement (TKR) is a common and costly procedure widely used to relieve pain and improve function in patients with symptomatic advanced knee osteoarthritis (OA). As of 2013, the annual incidence of TKR was over 680,000 surgeries and annual costs exceeded $11 billion. Growing evidence suggests that while pain and functional status improve following TKR, physical activity (PA) typically does not surpass pre-TKR levels. Engagement in PA can meaningfully improve quality of life (QoL), pain, and function. Given the large investment in TKR, the effectiveness and cost-effectiveness of TKR could be substantially increased if TKR recipients became more physically active. The Knee Arthroplasty Activity Trial (KArAT) is a randomized controlled trial and participants will be randomly assigned to one of three arms. Participants across all arms will receive usual post-operative care for TKR surgery. Participants in the first arm will complete basic study activities, such as responding to surveys and attending two in-person clinic visits. Participants in the second arm will do the same and also receive a wrist-based physical activity tracker intervention. Participants in the third arm will receive a telephonic active coaching (motivational interviewing) and financial incentives (for reaching physical activity goals) (TAC(MI)+FI) based intervention, as well as a wrist-based physical activity tracker intervention. The second and third arms will be eligible to receive lottery-based financial rewards for wearing a wrist-worn activity tracker for twenty-four months during the study.
Conditions Studied
Interventions
- BEHAVIORAL Telephonic Active Coaching (Motivational Interviewing) + Financial Incentives
- BEHAVIORAL Wrist based activity tracker wear
- OTHER Basic Study Activities
Study Locations (5)
Illinois
- Northwestern Memorial Hospital — Chicago
Kansas
- University of Kansas Medical Center — Kansas City
Massachusetts
- Brigham and Women's Hospital — Boston
Nebraska
- University of Nebraska Medical Center — Omaha
New York
- University at Buffalo — Buffalo
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 600 participants |
| Start Date | 2023-04-27 |
| Est. Completion | 2028-06-15 |
| Phase | NA |
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Full Details on ClinicalTrials.gov ↗What the Registry Record Tells You About NCT04107649
The ClinicalTrials.gov registry entry for NCT04107649 describes a study currently listed as active not recruiting. It is categorized as NA, which is the standard way researchers label where a study sits along the investigational pathway from early safety work through later efficacy and post-marketing evaluation. The registered enrollment target is 600 participants, a figure that helps gauge the scale of data the investigators plan to collect. The listed sponsor is Brigham and Women's Hospital, which has 929 total studies on file at ClinicalTrials.gov, and sponsors are the parties responsible for study design, oversight, and regulatory filings.
The record links to 2 conditions, with Knee Osteoarthritis appearing as the primary indexed condition, and to 3 interventions — of which Telephonic Active Coaching (Motivational Interviewing) + Financial Incentives is the first listed. Interventions can include drugs, devices, procedures, behavioral programs, or observational arms, and each is tracked as a separate registry field so that downstream queries can filter accurately. When a trial lists multiple interventions, it usually reflects a multi-arm design or a comparison protocol rather than a single treatment being tested in isolation. The brief summary published in the registry is the clearest source of protocol intent and should be read before drawing conclusions from any sidebar tags.
Geographic footprint matters for practical reasons: NCT04107649 reports 5 study locations spanning 5 distinct geographic areas — top geographies include Illinois, Kansas, Massachusetts. A larger site network tends to correlate with broader recruitment capacity, but it does not imply anything about study quality, and site-level enrollment status can diverge from the overall registry status shown above. Every data point on this page comes from the public ClinicalTrials.gov dataset and is reproduced here for reference only; it is not a medical recommendation, an endorsement of the sponsor, or an invitation to enroll. Verify current status, eligibility criteria, and contact details directly at ClinicalTrials.gov, and discuss any participation decision with your own healthcare provider.
Frequently Asked Questions
What is clinical trial NCT04107649 about?
NCT04107649 is a clinical study titled "Knee Arthroplasty Activity Trial". Total knee replacement (TKR) is a common and costly procedure widely used to relieve pain and improve function in patients with symptomatic advanced knee osteoarthritis (OA). As of 2013, the annual incidence of TKR was over 680,000 surgeries and annual costs exceeded $11 billion. Growing evidence su...
What is the current status of trial NCT04107649?
This trial is currently active not recruiting. It is a NA study. The enrollment target is 600 participants. The study started on 2023-04-27. Estimated completion is 2028-06-15.
What conditions does trial NCT04107649 study?
This clinical trial studies the following conditions: Knee Osteoarthritis, Total Knee Replacement. These conditions were identified from the trial registry and reflect the primary focus areas of the research.
What interventions are being tested in trial NCT04107649?
The interventions under investigation include: Telephonic Active Coaching (Motivational Interviewing) + Financial Incentives (BEHAVIORAL), Wrist based activity tracker wear (BEHAVIORAL), Basic Study Activities (OTHER). Each intervention is being evaluated for safety and efficacy as part of this clinical study.
Who is sponsoring clinical trial NCT04107649?
This trial is sponsored by Brigham and Women's Hospital, which has 929 total clinical trials registered on ClinicalTrials.gov. The sponsor is responsible for the study's design, funding, and regulatory compliance.
Where is trial NCT04107649 being conducted?
This trial has 5 study locations across Illinois, Kansas, Massachusetts, Nebraska, New York. Contact the study sites directly through ClinicalTrials.gov for enrollment availability.
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