MRI of Hoffa?s fat pad

Hyperintense signal alteration in the suprapatellar fat pad on MRI is associated with degeneration of the patellofemoral joint over 48 months: data from the Osteoarthritis Initiative

“…Articular fat pads are structurally similar to subcutaneous tissue [43], and it is assumed that they contribute to joint lubrication, stability, and absorption of forces generated in the moving joint [4][5][6][7]. For the infrapatellar fat pad, it has been shown that acute or repetitive trauma or surgery can induce hemorrhage and inflammation [6,44], subsequently leading to hypertrophy and impingement [16].…”

“…For the infrapatellar fat pad, it has been shown that acute or repetitive trauma or surgery can induce hemorrhage and inflammation [6,44], subsequently leading to hypertrophy and impingement [16]. It has been shown that an increase in signal intensity on fluid-sensitive fat-saturated sequences, representing an increase in tissue fluid referred to as edema, is sensitive in the acute phase of the disease [4,5,45]. More recently, it has been suggested that the infrapatellar fat pad also plays a relevant role in the development of OA [1][2][3].…”

“…Most studies have focused on the infrapatellar or Hoffa's fat pad, considering it to be relevant for the progression of knee osteoarthritis [1][2][3]. It has been suggested to contribute to joint lubrication and to absorb loading forces [4][5][6][7]. Associations of infrapatellar fat pad imaging findings and joint degeneration have been inconsistent, with an increase in the volume of Hoffa's fat pad being associated with either accelerated [8] or slowed cartilage degeneration [9], and signal intensity alterations associated with worsening of clinical symptoms and knee OA imaged with MRI [3].…”

“…It fills the gap between the quadriceps tendon, the retropatellar cartilage, and the suprapatellar joint recess, which separates it from the prefemoral fat pad [10][11][12][13]. Like the impingement syndrome of the infrapatellar fat pad, also known as Hoffa's disease [4,5,[14][15][16], abnormalities may also be found in the SPFPs that have typical MRI findings and may be associated with clinical symptoms [10,11,17,18]. However, data on the relevance of MRI findings of the SPFPs in OA are scarce.…”

Qual O Seu Diagnóstico?

“…When signal abnormalities follow the course of the infrapatellar plica (a line extending from the inter-condylean sulcus to the retropatellar fat tissue, parallel to the anterior cruciate ligament), most probably the diagnosis is plica syndrome. More diffuse abnormalities affecting the whole posterior aspect of the infrapatellar fat pad indicate the diagnosis of Hoffa's disease (9) . Other differential diagnoses to be considered are: synovial chondromatosis, pigmented villonodular synovitis, calcinosis, osteochondrosis, calcareous tendinopathy, femur, tibia or even patella tumors with infrapatellar fat tissue invasion, and, even though extremely rare, primary chondrosarcomas of the Hoffa's fat pad.…”