Clinical Trial Details
— Status: Completed
Administrative data
| NCT number |
NCT05659316 |
| Other study ID # |
RGDS-2019-12-064 |
| Secondary ID |
|
| Status |
Completed |
| Phase |
|
| First received |
|
| Last updated |
|
| Start date |
April 15, 2022 |
| Est. completion date |
May 30, 2023 |
Study information
| Verified date |
April 2024 |
| Source |
GCS Ramsay Santé pour l'Enseignement et la Recherche |
| Contact |
n/a |
| Is FDA regulated |
No |
| Health authority |
|
| Study type |
Observational
|
Clinical Trial Summary
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.
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.
