BACKGROUND: Periprosthetic fracture after total knee arthroplasty (TKA) is an increasingly recognized condition with several associated risk factors such as osteoporosis, rheumatoid arthritis, corticosteroid therapy, and anterior femoral notching. With a reported incidence of 0.3-2.5% for supracondylar femoral fractures following TKA, the majority of these fractures occur following minor trauma such as a fall. Surgical management in this case was guided by the Su classification system in addition to the fracture pattern, quality of bone, presence of other femoral implants, and general health of the patient. The purpose of this video was to demonstrate the surgical technique in the case of a comminuted interprosthetic fracture of the femoral shaft.METHODS: This video presents the surgical repair of an interprosthetic femoral shaft fracture using direct open reduction. The fracture was classified as type I since both femoral and knee prostheses were well fixed. A femoral locking plate with lag screw fixation was used to achieve successful fixation. Relevant patient history, imaging, surgical considerations, surgical technique, and postoperative rehabilitation are reviewed. The major features of the technique are highlighted and the rationale behind the approach is discussed.RESULTS: The Su classification can be used for operative planning for periprosthetic femoral shaft fractures. This video demonstrates successful reduction and fixation of a periprosthetic femoral shaft fracture. Fracture reduction is confirmed with postoperative imaging.CONCLUSION: Periprosthetic femoral shaft fractures are a complicated clinical entity that requires extensive surgical planning. With a variety of surgical options available, both the status of the prosthesis and the displacement of the fracture must be considered. Direct open reduction using a femoral locking plate can be used to successfully repair a comminuted interprosthetic femoral shaft fracture.