The main fat pad - or Hoffa's fat pad - in the knee is an area of cushioning fatty tissue behind the patellar tendon - but there are also other fat pads in the knee above the patellar area.
The three main fat pads in the knee.
The Hoffa fat pad may be structurally connected to the infrapatellar plica and be stretched with movement.
Suprapatellar, prefemoral and infrapatellar (Hoffa) fat pads
The Hoffa's fat pad is also known as the infrapatellar fat pad because of its situation below the patella. The other two notable fat pads are found above the patella, where they cushion the area behind the quads tendon in front of the femur. Because the fat pads are flexible, they change shape as the knee bends and straightens.
MRI Findings Consistent with Peripatellar Fat Pad Impingement: How Much Related to Patellofemoral Maltracking? Jarraya M, Diaz LE, Roemer FW, Arndt WF, Goud AR and Guermazi A. Magn Reson Med Sci. 2018; 17(3): 195–202.
Hoffa’s fat pad abnormalities, knee pain and magnetic resonance imaging in daily practice Draghi F, Ferrozzi G, Urciuoli L, Bortolotto C and Bianchi S. Insights Imaging. 2016 Jun; 7(3): 373–383.