DISTAL FEMUR FRACTURES AND AUGMENTATION: A RETROSPECTIVE REVIEW

The purpose of this study was to compare the reoperation rates, union rates, and complications of various constructs used in the surgical fixation of native and periprosthetic distal femur fractures to determine the ideal construct and augmentation required. Retrospective review of patients treated with operative fixation of the distal femur between 2016 and 2022 at our hospital were identified using population-level administrative data. Radiographic screening and chart review of patients was carried out to identify their initial surgical construct and fracture characteristics. Chart reviews followed to determine patient characteristics and the indications for reoperation and other post-operative complications. The main outcome measures were reoperation rates and their indications. From 2016–2022, 110 patients with 117 distal femur fractures were operated on with one of the following initial constructs: 81 lateral plating (69.2%), nine dual plates (7.7%), 13 intramedullary nail (11.1%), four plate-nail combination (3.4%), eight far cortical locking plating (6.8%), one medial plating (0.01%), and one distal femoral replacement (0.01%). The average age of included patients was 65.8 (SD, 22.8). Reoperation was required in 23 patients (19.7%) for non-union, hardware irritation, infection, and hardware failure or periprosthetic fracture. Patients who required reoperation were significantly younger (54.1 [SD, 18.5] vs 68.9 [SD, 23.2]; P = 0.001), and had significantly higher rates of 33-C3 fractures (39.1% vs 14.9%; P = 0.026) and presence of medial comminution (52.2% vs 16.0%; P = 0.001). A multivariate logistic regression model demonstrated an increased odds ratio for overall reoperation in patients with the presence of medial comminution (OR, 2.23 [95% CI, 1.13–5.35]; P = 0.001) and an increased likelihood of medial comminution leading to non-union (OR, 6.94 [95% CI, 2.27–8.38], P = 0.017). There were 20 patients (18.2%) who expired within six months of sustaining their injury. The presence of medial comminution in the distal femur fracture was significantly associated with requiring reoperation and developing non-union. The severity of the initial fracture was significantly associated with reoperation. Increasing age was significantly associated with decreased risk of reoperation. Patients with severe fractures, osteoporosis, and/or medial comminution would benefit from some form of augmentation with their initial surgical construct. Mortality rates within 6 months were high and may be comparable to hip fracture mortality. Looking at time to surgery for these patients would be crucial in determining the ideal window of time to management.