Knee Positioning After Total Knee Replacement

NCT07747116 | Not Yet Recruiting

• 1 other identifier: Study 26-00680
• Study Type: interventional
• Target: 150
• Locations: 1 country
• Sites: 1

Brief Summary

Many total knee replacements are performed each year, but there is no clear recommendation regarding knee positioning following this surgery. While the surgical knee is usually positioned in a straight position immediately after surgery, there may be benefits of positioning it in a partially bent position. A trial will compare the outcomes of two groups of patients: a) those whose knees are positioned in a partially bent position for a few hours after surgery and b) those who receive usual care where the knee is most likely positioned in a straight position. The investigators are looking to see whether knee motion and pain differ for patients in the two groups.

Conditions

Knee Arthroplasty

Keywords

Knee Flexion

Outcome Measures

Primary Outcomes (2)

• Knee Passive Total Arc of Motion

  Passive total arc of motion will be evaluated through goniometric assessment of maximal passive knee flexion and passive knee extension. Both measures will be recorded, but a single endpoint will be derived by subtracting available extension from available flexion.

  At 6 weeks after surgery

• Maximum Pain Intensity

  Pain intensity will be evaluated via the patient-reported Numeric Rating Scale (NRS) for pain. The rating is from 0 to 10, with a higher score indicating worse pain. The worst (i.e., maximum) pain intensity will be used.

  At 7 days after surgery

Secondary Outcomes (19)

• Knee Passive Total Arc of Motion

  At 2.5 weeks, 3 months, 6 months, and 12 months after surgery

• Maximum Pain Intensity

  At 0 days, 1 day, 2 days, 3 days, 10 days, 14 days, 2.5 weeks, 6 weeks, 3 months, 6 months, and 12 months after surgery

• Total Opioid Consumption

  Postoperative days 0 through 14

• Knee Injury and Osteoarthritis Outcome Score for Joint Replacement

  At 6 weeks, 3 months, 6 months, and 12 months after surgery

• Veterans RAND 12-item Health Survey

  At 6 weeks, 3 months, 6 months, and 12 months after surgery

Study Arms (2)

Knee Flexion

EXPERIMENTAL

Participants in this arm will receive the knee flexion intervention.

Other: Knee Flexion

Usual Care

ACTIVE COMPARATOR

Participants in this arm will receive usual care. No specific attention will be placed to knee positioning in the immediate period after surgery. However, the current usual practice in the health system is that the knee is positioned in extension.

Procedure: Standard Care

Interventions

Knee Flexion OTHER

Participants will receive knee flexion postoperatively following primary total knee arthroplasty. The surgical knee will positioned at approximately 60° flexion using an abduction pillow as a jig underneath the knee during the immediate postoperative recovery period. Positioning will occur following surgery while the participant is still in the operating room. This is a soft construct and a noninvasive intervention. A goniometer will be used to approximate 60° of flexion as closely as possible. It is expected that the knee will be positioned for 2-4 postoperative hours until a physical therapist comes to mobilize the patient. However, the duration may vary because of the pragmatic context. There is no minimum or maximum positioning time that would make the intervention duration ineligible.

Knee Flexion

Standard Care PROCEDURE

Participants in this arm will receive usual care. No specific attention will be placed to knee positioning in the immediate period after surgery. However, the current usual practice in the health system is that the knee is positioned in extension.

Usual Care

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Provision of signed and dated informed consent form
• Stated willingness to comply with all study procedures and availability for the duration of the study
• Males and females; Age \>18 years
• Scheduled for elective primary unilateral total knee arthroplasty
• The planned arthroplasty is secondary to physician-confirmed diagnosis of knee osteoarthritis
• English- or Spanish-speaking

You may not qualify if:

• Patients with a history of chronic opioid use or chronic pain disorders
• Patients with a history of bleeding disorders/coagulopathy
• Patients receiving a total knee replacement secondary to trauma, avascular necrosis, tumor, or Charcot arthropathy
• Patients scheduled to undergo multiple procedures simultaneously
• Patients with cognitive impairment or inability to consent independently

Sponsors & Collaborators

• Icahn School of Medicine at Mount Sinai: lead

Study Sites (1)

Mount Sinai Health System

New York, New York, 10029, United States

Location

MeSH Terms

Interventions

Standard of Care

Intervention Hierarchy (Ancestors)

Quality Indicators, Health Care; Quality of Health Care; Health Services Administration; Health Care Quality, Access, and Evaluation

Study Officials

• Brett Hayden, MD

  Icahn School of Medicine at Mount Sinai

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Brocha Stern

CONTACT

212-659-9650; brocha.stern@mountsinai.org

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: CARE PROVIDER
• Masking Details: Participant arm assignment will be concealed from the surgeon who will leave the operating room before the knee is positioned. The surgeon will also be the assessor of the primary 6-week knee total arc of motion endpoint. The patient and investigators assessing other endpoints will not be masked to the arm.
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Assistant Professor

Study Record Dates

• First Submitted: July 30, 2026
• First Posted: August 5, 2026
• Study Start: September 1, 2026
• Primary Completion (Estimated): February 1, 2028
• Study Completion (Estimated): February 1, 2029
• Last Updated: August 5, 2026

Record last verified: 2026-07

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)