RecruitingPhase 4Drug trialHoffa's Fat Pad Impingement (HFPI)The aim of the study is to investigate treatment outcomes for refractory anterior knee pain due to Hoffa's Fat Pad Impingement (HFPI) in young female athletes. Specifically, the study team will study pediatric female athletes with HFPI, and treatment outcomes of US-guided Hoffa's Fat Pad (HFP) corticosteroid injection compared to standard care (physical therapy, bracing, no injection) and saline injection. There will be two arms in this study, 1, a corticosteroid injection and physical therapy and 2, physical therapy and a saline injection. The intent of this study is to measure treatment outcomes, and the research team is not looking at the safety and effectiveness of the lidocaine-methylprednisolone mixture.