NCT07625150

Brief Summary

This project aims to develop an \[18F\] fluorodeoxyglucose (FDG) positron emission tomography (PET) / magnetic resonance imaging (MRI) method to locate the painful inflammation in PFJ OA associated with joint loading. \[18F\] FDG PET/MRI is an emerging pain imaging approach with enhanced sensitivity to painful hypermetabolic inflammation through evaluation of intracellular glucose utilization rate via (\[18F\]FDG PET) and fine anatomy details (MRI). The investigative group has shown its promise in revealing previously unidentified or unspecified pain generators in various musculoskeletal pain conditions. The investigators have also demonstrated the feasibility of visualizing the structural changes between unloaded and loaded knee joints with MRI, which can be easily adopted in the current PET/MRI setting. The main challenge in the proposed \[18F\]FDG PET/MRI approach is to differentiate the normal uptake of FDG for metabolic changes by weight-bearing from abnormal changes indicating eventual pain aggravation by weight-bearing and knee-flexion. The investigators have garnered the following two aims to validate the proposed method by comparing unloaded and loaded knee imaging results between PFJ OA pain patients and asymptomatic, matched controls.

Trial Health

77
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
50

participants targeted

Target at P25-P50 for all trials

Timeline
20mo left

Started Feb 2025

Typical duration for all trials

Geographic Reach
1 country

1 active site

Status
recruiting

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

Study Progress45%
Feb 2025Feb 2028

Study Start

First participant enrolled

February 19, 2025

Completed
1.3 years until next milestone

First Submitted

Initial submission to the registry

May 22, 2026

Completed
13 days until next milestone

First Posted

Study publicly available on registry

June 4, 2026

Completed
1.7 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

February 1, 2028

Expected
Same day until next milestone

Study Completion

Last participant's last visit for all outcomes

February 1, 2028

Last Updated

June 4, 2026

Status Verified

June 1, 2026

Enrollment Period

3 years

First QC Date

May 22, 2026

Last Update Submit

June 1, 2026

Conditions

Patellofemoral OsteoarthritisKnee OsteoarthritisInflamationKnee Pain

Outcome Measures

Primary Outcomes (2)

  • Maximum Standardized Uptake Value (SUVmax) of [18F]FDG in PFJ Tissues, Pre-Loading

    Comparison of FDG SUVmax between PFJ OA patients and asymptomatic controls across various tissue types (synovium, femur, tibia, meniscus, fat pad, and muscles) to identify hypermetabolic inflammation at pre-loading.

    baseline, pre-loading

  • Maximum Standardized Uptake Value (SUVmax) of [18F]FDG in PFJ Tissues, Post-Loading

    Comparison of FDG SUVmax between PFJ OA patients and asymptomatic controls across various tissue types (synovium, femur, tibia, meniscus, fat pad, and muscles) to identify hypermetabolic inflammation at post-loading.

    baseline, post-loading

Secondary Outcomes (2)

  • Change in SUVmax Between Unloaded and Loaded States

    baseline

  • Visual Analog Scale Maximum Pain Score During a Single-Leg Squat

    baseline

Study Arms (2)

PFJ OA Patients

Group defined as WORMS 2-6, and \>1 VAS pain during 25 single-leg squats

Healthy Controls

Healthy volunteers with WORMS 0-1, and 0-1 VAS pain during 25 single-leg squats

Eligibility Criteria

Age18 Years+
Sexall
Age GroupsAdult (18-64), Older Adult (65+)
Sampling MethodNon-Probability Sample
Study Population

The study population includes outpatient individuals with patellofemoral joint osteoarthritis (PFJ OA) and healthy asymptomatic volunteers recruited from the University of California, San Francisco (UCSF) and the surrounding community

You may qualify if:

  • Adult with the capacity to give informed consent
  • Ability to perform 25 single-leg squats
  • No traumatic knee injuries/surgeries since last visit for the parent study (IRB #21-34763)
  • No investigational drugs since last visit for the parent study (IRB #21-34763)
  • No contraindications to MRI or PET tracer since last visit for the parent study (IRB #21-34763)
  • Not taking steroid injections
  • Not pregnant

You may not qualify if:

  • Inability to consent for themselves
  • Inability to perform 25 single-leg squats with the study leg
  • New traumatic knee injuries/surgeries since last visit for the parent study (IRB #21-34763)
  • Taking investigational drugs since last visit for the parent study (IRB #21-34763)
  • New contraindications to MRI or PET tracer since last visit for the parent study (IRB #21-34763)
  • Taking steroid injections
  • Pregnant
  • Diabetic

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

UCSF Radiology China Basin

San Francisco, California, 94107, United States

RECRUITING

MeSH Terms

Conditions

Osteoarthritis, Knee

Condition Hierarchy (Ancestors)

OsteoarthritisArthritisJoint DiseasesMusculoskeletal DiseasesRheumatic Diseases

Study Officials

  • Richard Souza, PhD, PT

    University of California, San Francisco

    PRINCIPAL INVESTIGATOR

Central Study Contacts

Eric Hammond

CONTACT

415-502-6470eric.hammond@ucsf.edu

Study Design

Study Type
observational
Observational Model
CASE CONTROL
Time Perspective
CROSS SECTIONAL
Sponsor Type
OTHER
Responsible Party
SPONSOR

Study Record Dates

First Submitted

May 22, 2026

First Posted

June 4, 2026

Study Start

February 19, 2025

Primary Completion (Estimated)

February 1, 2028

Study Completion (Estimated)

February 1, 2028

Last Updated

June 4, 2026

Record last verified: 2026-06

Data Sharing

IPD Sharing
Will not share

Locations

US(1)