Hoffa fat pad herniation

Hoffa fat pad herniation is defined as herniation of infrapatellar fat through a defect in the lateral retinaculum. It is an uncommon cause of an anterolateral knee mass often detected at the fully flexed knee 1.

Clinical presentation

Mainly occurs in preschool-aged and young children as a painless soft mass along the anterolateral aspect of knee joint due to a focal defect in the lateral retinaculum.

In one of the recent MRI knee study, the focal defect in the lateral patellar retinaculum was found with 26% frequency. It was suggested as a normal variant rather than a pathologic change 2.

Knee pathology

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

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Article information

rID: 56605
Synonyms or Alternate Spellings:
  • Infrapatellar fat pad herniation
  • Infrapatellar fat herniation
  • Focal herniation of Hoffa’s fat pad

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Cases and figures

  • Case 1: on ultrasound
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