Localized nodular synovitis of the infrapatellar fat pad.

We report a case of localized nodular synovitis of the infrapatellar fat pad impinging on the patellofemoral joint causing limitation of extension. Arthroscopy involved use of a superolateral portal because location of lesion hindered access via a conventional anterior portal. The infrapatellar mass impinged in the patellofemoral joint upon knee extension and retracted upon flexion. Superior-superior triangulation allowed for complete excision of the mass.