A Case of Prefemoral Fat Pad Impingement Syndrome Caused by Hyperplastic Fat Pad

Case. We report a rare case of prefemoral fat pad impingement syndrome that was caused by a hyperplasia of the normal suprapatellar fat pad. Pain and catching were observed in the proximal-lateral patellofemoral joint, and MRI imaging confirmed a hyperplasic mass in the same area. Although conservative treatment showed no signs of improvement, symptoms improved after an arthroscopic excision of the mass. Conclusion. Prefemoral fat pad impingement syndrome is related to patellar motion and should be considered as one of the underlying causes of anterior knee pain (AKP). Surgeons should recognize that a small hyperplasia composed of normal adipose tissue can cause AKP.