About weight-bearing ultrasound study of patellar tendon.
Take a look at this clinical case in which the patient with a clear evidence of patella alta and lateral patellar compression syndrome, has a tendinopathy of the patellar tendon at its proximal insertion, with chronic anterior knee pain and instability.
Sagittal T1w and Stir Mri sequences (0.3 tesla).
In orthostatism is most evident the increase of flow in vessels that are dilated because of inflammatory response.
This is the reason why I always perform the ultrasound examination both in clino and in orthostatism. Have you ever tried?
Dynamic Mri exam is crucial in many situations; in a previous post I have shown a dynamic Mri study of patellofemoral impingement with patella alta.
Take a look at this patient in which the suspected patella baja is well studied during flexion-extension active movements.
The Insall-Salvati Index (ISI) and its modified version are used the same way on Mri studies as on plain radiographs.
Rember that in case of true patella baja, the patella remains engaged within the trochlear groove in full knee extension. The dynamic examination allows to appreciate the direct visualization of patellar and trochlear allignment for a more objective measurement, together with the others modalities. In this patient the dynamic examination shows a correct patellar positioning during active extension.