Research Award Details

2020 - POSNA Micro Grant

Trochlea US


Grant Recipient: Aharon Gladstein, MD

Institution:
Baylor College of Medicine
Additional Information:
Date: August 1, 2021
Project Title: Validation of Ultrasound Use for Evaluation of the Femoral Trochlea
Investigators: Aharon Gladstein, Erica Schallert, ElSayed Attia
Location: Texas Children’s Hospital/Baylor College of Medicine, Houston TX

Final Report

Project Summary: The award was put toward performing focused ultrasound (US) of the femoral trochlea in pediatric patients undergoing magnetic resonance imaging (MRI) of the knee. 10 patients underwent ultrasound along with knee MRI. We hypothesized that there will be: i) excellent correlation between MRI and US measurements of trochlear sulcus angle and facet asymmetry in children; ii) good correlation between MRI and US measurements of trochlear depth and lateral facet inclination in children.

Successes (what worked): We were able to recruit patients to the study with relative ease after COVID-19 restrictions were lightened. Patients were very willing when the purpose of the study was explained. Ultrasound is a familiar test due to its use in obstetrics. Families felt comfortable with it in general.
Challenges (what did not work): It took longer than expected to enroll patients. At the outset of COVID-19, there were much fewer knee MRIs ordered for injury. Of those patients sent for MRI, it took some months before it seemed sensible to ask patients and our radiology staff to volunteer for an additional exposure.

In addition, we were quoted a cost for each ultrasound study, but as the project went on, we were informed that the cost was actually higher than what we were told. We had to do some maneuvering to make sure that the project was funded. In the future, we need a more concrete cost-per-study, in writing, to pursue further similar projects.

Was our Primary Outcome Measure Successful? We had hoped to show excellent correlation between MRI and US measurements of trochlear morphology. Our data showed that ultrasound and MRI had excellent correlation for the following variables:
  • Sulcus angle
  • Facet asymmetry
  • Trochlear depth
  • Facet inclination
There were no tested variables for which US and MRI did not have excellent correlation.

Future Plans: We plan to submit an abstract for the POSNA 2022 annual meeting. In preparation, we will have additional readers interpret the images in a similarly blinded manner to show interobserver reliability data. We also plan to apply for additional grant funding, through POSNA, to perform more ultrasound studies to better solidify our technique and analyze its diagnostic utility. The opportunity to devise the project and see it through has been very fulfilling. The ultimate goal would be to follow patients longitudinally after early intervention for patellar instability and use this technique to assess trochlear development. We hope to use the opportunity to add to our body of knowledge about patellofemoral disorders.