Patient Positioning
Patient lies supine, knee 20°–30° flexed. Place a small pillow under the joint to keep this position.
Probe Positioning
Place the transducer on a sagittal plane in the midline over the quadriceps tendon and the cranial part of the patella (landmark).
Note: Enthesitis of the quadriceps tendon in spondyloarthritis with hypoechoic swelling of the tendon and enthesis and positive doppler signal.