Fig. 2.

Illustration of the changes in position, shape and morphology of the peripatellar fat pads in extreme flexion of the knee. The suprapatellar fat pad (solid straight arrow) interposes between the quadriceps tendon anteriorly, and femoral condyle posteriorly; the prefemoral fat pad (empty arrow) interposes between the quadriceps tendon anteriorly, and the distal shaft of the femur posteriorly; and the infrapatellar fat pad (Hoffa fat pad) (curved arrow) interposes between the patellar ligament anteriorly, and superior tibia posteriorly.