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.
Page updated February 2024 by Dr Sheila Strover (Clinical Editor)
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.
Which is the most important fat pad?
There are three fat pads in the knee, and the most important is the Hoffa fat pad.
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.
Why is the Hoffa fat pad significant?
The significance of the fat pads of the knee is still poorly appreciated. They are frequently traumatised in accidental injuries, but also during knee surgery, leading to distressing anterior knee pain.
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Quote from peer-reviewed paper:
"...the [infrapatellar plica] is abundantly vascularized and innervated....[with]....a high density of sensory innervation....[It] is covered with a synovial membrane [and] is connected to the intercondylar region and the synovial tube of the anterior cruciate ligament via the infrapatellar plica....[and]....attached to the anterior roots of both menisci...."
Citation: Braun S, Zaucke F, Brenneis M, Rapp AE, Pollinger P, Sohn R, Jenei-Lanzl Z, Meurer A. The Corpus Adiposum Infrapatellare (Hoffa's Fat Pad)-The Role of the Infrapatellar Fat Pad in Osteoarthritis Pathogenesis. Biomedicines. 2022 May 5;10(5):1071. doi: 10.3390/biomedicines10051071. PMID: 35625808; PMCID: PMC9138316.
Fat pad syndrome
The fat pad syndrome, or Hoffa's syndrome, is a painful condition where the fat pad is impinged and traumatised, swelling up and making the situation worse.
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Quote from peer-reviewed paper:
"....evidence suggests that high patellar height, TT-TG distance, and trochlear angle predispose the development of Hoffa’s fat pad syndrome."
Citation: Abelleyra Lastoria DA, Benny CK, Hing CB. Predisposing factors for Hoffa's fat pad syndrome: a systematic review. Knee Surg Relat Res. 2023 Jun 9;35(1):17. doi: 10.1186/s43019-023-00192-4. PMID: 37296488; PMCID: PMC10251569.
Fat pad excision
The fat pad is often surgically removed to gain access to the knee joint.
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Quote from peer-reviewed paper:
"...the [infrapatellar fat pad - IFP] is (partially) resected in most total knee arthroplasties (TKA) allowing better visualization during surgical procedures. Currently, there is no clear guideline providing evidence in favor of or against IFP resection...."
Citation: Braun S, Zaucke F, Brenneis M, Rapp AE, Pollinger P, Sohn R, Jenei-Lanzl Z, Meurer A. The Corpus Adiposum Infrapatellare (Hoffa's Fat Pad)-The Role of the Infrapatellar Fat Pad in Osteoarthritis Pathogenesis. Biomedicines. 2022 May 5;10(5):1071. doi: 10.3390/biomedicines10051071. PMID: 35625808; PMCID: PMC9138316.
Forum discussions
- Bad Case of Fat Pad Impingement...
A full discussion about fat pad problems.
Relevant material -
- Fat pad syndrome
- Hoffa's disease
- Patellofemoral pain syndrome
- Anterior knee pain
- IPP-Fat pad Complex
From the Experts -
- Expert view - 2018 - An alternative viewpoint on Anterior Knee Pain - by Dr Thomas Smallman (Knee Surgeon)