Fat pad impingement syndromes of the knee

Dr Henry Knipe et al.

In fat-pad impingement syndromes, the etiologies are different for each knee fat pad.

In anterior suprapatellar fat pad impingement syndrome, the cause is usually due to either a developmental cause related to the anatomy of the extensor mechanism or may be related to abnormal mechanics. In this syndrome, the posterior border of the anterior suprapatellar (quadriceps) fat pad is high signal on PD MRI and convex with a mass effect upon the suprapatellar bursa.

In infrapatellar fat pad impingement syndrome (Hoffa disease) the cause is usually due to single or repetitive traumatic episodes; the inflamed fat pad then becomes hypertrophied with a predisposition to impingement between the tibia and femur, and thus to further injury (a vicious circle).

Knee pathology

The knee is a complex synovial joint that can be affected by a range of pathologies:

Article information

rID: 23377
Section: Syndromes
Synonyms or Alternate Spellings:

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Cases and figures

  • Case 1: suprapatellar fat pad impingement syndrome
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  • Case 2: suprapatellar fat pad impingement
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  • Case 3: chronic Hoffa impingement syndrome
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  • Case 4: Hoffa's fat pad impingement syndrome - ultrasound
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  • Case 5: Hoffa's fat pad impingement syndrome
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  • Case 6: anterior suprapatellar fat pad impingement syndrome
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