Hoffa fat pad ganglion cyst

Last revised by Mostafa Elfeky on 16 May 2024

Hoffa fat pad ganglion cysts are intra-articular ganglion cysts and are the most common mass-like lesions within the Hoffa fat pad.

Hoffa fat pad ganglion cysts are rare and less common than cruciate ligament ganglion cysts 1,2.

Ganglia within Hoffa’s fat pad can be asymptomatic or can cause pain and swelling or present as a palpable mass 1,2.

Ganglion cysts within Hoffa’s fat pad are usually well-defined, smooth-walled, uni- or multilocular, lobulated cystic masses surrounded by dense connective tissue and filled with viscous, mucinous material like other ganglion cysts. They lack a synovial membrane 1-3.

Like with other ganglion cysts, the pathogenesis is controversial and comprises the following theories 2-4:

  • a sequel of mucoid degeneration

  • cyst formation as a consequence of trauma or tissue irritation

  • release of hyaluronic acid by mesenchymal stem cells and consecutive cyst formation

  • synovial herniation

  • congenital translocation of synovial cells

Ganglion cysts of Hoffa’s fat pad are usually located anterior to the anterior horn of the lateral meniscus 1.

MRI is the best modality for the visualization and evaluation of intra-articular ganglion cysts. The typical appearance is that of a well-defined lobular cystic mass within or adjacent to Hoffa’s fat pad 1,2,4.

  • T1: usually hypointense but will depend on protein content

  • T2: hyperintense

  • PDFS/T2FS: hyperintense

Management options depend vastly on clinical symptoms and include conservative measures, image-guided percutaneous aspiration as well as arthroscopic or surgical excision 2,4-6.

The differential is that of cyst-like lesions around the knee:

ADVERTISEMENT: Supporters see fewer/no ads