Patient #24, a 39-year-old female with giant cell tumor of the right distal femur treated with distal femur replacement in 2016. She developed arthrofibrosis and underwent revision in December, 2018 and developed an methicillin sensitive Staphylococcus aureus (MSSA) infection which necessitated debridement, antibiotics and implant retention (DAIR) in January, 2019. She received multiple antibiotics due to intolerability. MSSA was again isolated during a second DAIR procedure in January 2020 and she required a third DAIR procedure in January 2020. She developed increased right leg pain and night sweats in March 2020 and an increase in inflammatory markers. Phage therapy was considered as a way to mitigate the infection and possibly thwart additional surgery (resection arthroplasty which would be highly disruptive and morbid). Aspiration of the right knee on 4/3/20 showed a WBC of 10,000 per cubic millimeter with 89% neutrophils and the culture was positive for MSSA. She was started on phage therapy on 4/3/20. She received a double dose IA and daily IV dosing. She did well clinically and reported 0 out of 10 pain. She is scheduled for repeat aspiration and the case is ongoing.