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).
SL: superficial layer (rectus femoris)
IL: intermediate layer (vastus lateralis and medialis)
DL: deep layer (vastus intermedius)
Note: the suprapatellar joint recess is best visible with slightly contracted quadriceps muscle / in mild knee flexion