Radiographic and Clinical Outcomes of Periprosthetic Distal Femur Fractures Treated With Open Reduction Internal Fixation

Objectives: To report outcomes and complications of periprosthetic distal femur fractures (PPDFF) treated with open reduction internal fixation (ORIF) using a plate construct, with or without endosteal augmentation. Design: Retrospective Case Series. Setting: One Level I trauma center and one tertiary care hospital. Patients/Participants: Forty patients with PPDFFs, treated by 3 surgeons, were identified using an institutional trauma registry. Thirty-two patients with 12 months of clinical and radiographic follow-up were included, and 8 patients were lost to follow-up before 12 months. Intervention: All patients underwent ORIF of the PPDFF with lateral locked plating, and 11 received additional endosteal augmentation using allograft fibula. Results: Thirty-two patients were available for the final follow-up. Ninety-four percent of patients achieved union at an average of 6.5 months postoperatively. Twenty-one percent of patients underwent subsequent surgery, with more than half of those being for removal of implants. Anatomic limb alignment was achieved in all cases (no malunions). Almost half of the patients required assistive devices for ambulation in the long term. Conclusions: ORIF of PPDFF with direct visualization using periarticular locking plates +/- endosteal strut allograft resulted in a 94% union rate and no deep infections. There was no difference in outcomes between groups treated with or without additional endosteal fibular allograft. However, these are catastrophic injuries in frail patients, and 20% of patients either died or were lost to follow-up, and almost half required an assistive device for ambulation after surgery despite restoration of limb alignment.