Soft Tissue Masses of the Knee Related to a Focal Defect of the Lateral Patellar Retinaculum.
Antoine MorauxStefano BianchiThomas Le CorrollerPublished in: Journal of ultrasound in medicine : official journal of the American Institute of Ultrasound in Medicine (2017)
We report on the imaging features of 6 soft tissue masses in the anterolateral aspect of the knee related to a focal defect of the lateral patellar retinaculum. In 4 patients (3 female and 1 male; 6-65 years) presenting with nontender palpable soft tissue masses in the anterolateral aspect of their knees, ultrasonography showed a focal defect of the lateral patellar retinaculum with herniation of the Hoffa fat pad, which was only visible in flexion. A magnetic resonance imaging examination performed in 1 case confirmed the defect in the lateral patellar retinaculum but did not show a mass, as the knee was examined only at 10° of flexion. The 2 remaining patients (one male and 1 female; 62 and 55 years) presented with soft tissue masses in their anterolateral knees in both flexion and extension. These masses were related respectively to a lipoma of the Hoffa fat pad and to a ganglion cyst, both herniated through a defect of the lateral patellar retinaculum. Our cases suggest that a focal defect of the lateral patellar retinaculum may be a route for Hoffa fat pad herniation as well as a route for superficial extension of infrapatellar fat lesions such as lipomas and ganglion cysts.
Keyphrases
- total knee arthroplasty
- anterior cruciate ligament
- soft tissue
- anterior cruciate ligament reconstruction
- magnetic resonance imaging
- contrast enhanced
- minimally invasive
- end stage renal disease
- adipose tissue
- newly diagnosed
- chronic kidney disease
- ejection fraction
- ultrasound guided
- fine needle aspiration
- fatty acid
- computed tomography
- patient reported outcomes
- magnetic resonance
- high resolution
- photodynamic therapy
- mass spectrometry
- case report
- optical coherence tomography
- optic nerve