New MRI Measurement of Patellar Height in Knee Extension - IES-EV Control Study

The measurement of the patellar height is essential to decide and quantify the surgical correction to be made. The classic index is that of Cato and Deschamps. It has the advantage of its simplicity, with the measurement on a simple profile radiograph of the ratio between the distance from the patella to the tibia and the length of the patella. However, it has the disadvantage of measuring this height in relation to the tibia when the dislocation is located at the level of the patello-trochlear joint. The MRI index of sagittal patellar engagement on the trochlea (IES), described in 2012, does not have this drawback but it does not appear to be reliable: its value depends, in fact, on the flexion of the knee. This flexion, required by the MRI, is variable and is not specified by the radiologist. It is due to the use of an "antenna" that surrounds and lifts the knee.

The hypothesis of the study is that it is possible to determine and validate a new IES, in knee extension and therefore reproducible, thanks to the measurement of knee flexion on MRI. The precise value of this flexion can allow a virtual correction of the original IES to obtain, by mathematical calculation, the new IES in virtual extension.

Study Overview

• Status: Completed
• Conditions: Knee Injuries
• Intervention / Treatment: Other: MRI imaging

Detailed Description

Patellar instability, usually manifested by recurrent patellar dislocations, is a complex multifactorial pathology. Its treatment associates surgical gestures chosen according to a precise evaluation of the factors of the instability. Five factors are decisive, varying from one subject to another: rupture of the medial patellofemoral ligament, dysplasia of the trochlea, excessive lateralization of the anterior tibial tuberosity (ATT), external torsion of the ATT and patella alta, object of this study. The patella, when it is alta, is an important factor of instability because it is abnormally located above the trochlea in extension of the knee and is no longer guided at the start of flexion: it risks not engaging in the trochlear rail and thus to dislocate at the start of flexion.

The measurement of the patellar height is essential to decide and quantify the surgical correction to be made. The classic index is that of Cato and Deschamps. It has the advantage of its simplicity, with the measurement on a simple profile radiograph of the ratio between the distance from the patella to the tibia and the length of the patella. However, it has the disadvantage of measuring this height in relation to the tibia when the dislocation is located at the level of the patello-trochlear joint. The MRI index of sagittal patellar engagement on the trochlea (IES), described in 2012, does not have this drawback but it does not appear to be reliable: its value depends, in fact, on the flexion of the knee. This flexion, required by the MRI, is variable and is not specified by the radiologist. It is due to the use of an "antenna" that surrounds and lifts the knee.

The hypothesis of the study is that it is possible to determine and validate a new IES, in knee extension and therefore reproducible, thanks to the measurement of knee flexion on MRI. The precise value of this flexion can allow a virtual correction of the original IES to obtain, by mathematical calculation, the new IES in virtual extension.

• Study Type: Observational
• Enrollment (Actual): 40

Contacts and Locations

• Study Contact: Name: AURELIE COURTIN; Phone Number: +33 1 87 86 22 79; Email: aurelie.courtin@ramsaysante.fr

Study Locations

• France
  • Antony, France
    • Hopital Prive d'Antony

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 16 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes

• Sampling Method: Non-Probability Sample

Study Population

Subject with knee MRI

Description

Inclusion Criteria:

• Subject, male or female, over 18 years old
• Subject with an MRI
• Subject without patellar pathology, in particular without patellar instability
• Subject having been informed and not objecting to the use of his data

Exclusion Criteria:

• None

Study Plan

How is the study designed?

Design Details

• Observational Models: Cohort
• Time Perspectives: Retrospective

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Healthy volunteers; Healthy volunteers without any patellar injury	Other: MRI imaging; Knee MRI imaging

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Index of sagittal engagement of the patella (IES)	Measurement of a MRI index of sagittal engagement of the patella (IES) in knee extension at 0°	1 day

Collaborators and Investigators

• Sponsor: GCS Ramsay Santé pour l'Enseignement et la Recherche

Study record dates

Study Major Dates

• Study Start (Actual): April 15, 2022
• Primary Completion (Actual): May 30, 2023
• Study Completion (Actual): May 30, 2023

Study Registration Dates

• First Submitted: December 13, 2022
• First Submitted That Met QC Criteria: December 13, 2022
• First Posted (Actual): December 21, 2022

Study Record Updates

• Last Update Posted (Actual): April 18, 2024
• Last Update Submitted That Met QC Criteria: April 17, 2024
• Last Verified: April 1, 2024

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Wounds and Injuries; Leg Injuries; Knee Injuries
• Other Study ID Numbers: RGDS-2019-12-064

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No