Nail Plate Constructs Permit Early Weight Bearing and Improved Outcomes Compared to Single Device Constructs in the Treatment of Distal Femur Fractures at One-Year Follow-Up: A Retrospective Analysis

OBJECTIVES: To investigate clinical, radiographic, and patient reported outcomes in patients undergoing surgical fixation for distal femur fractures (DFFs) with single device construct (lateral locked plate or intramedullary nail (IMN)) or nail-plate combination. METHODS: Design: Retrospective cohort study. SETTING: Single, academic, tertiary Level I trauma center. PATIENT SELECTION CRITERIA: The inclusion criteria were patients with distal femur fractures (OTA/AO 33) treated operatively with lateral locked plate, IM Nail, or nail-plate combination between 01/2011 and 12/2023 with a minimum follow up of one year. OUTCOME MEASURES AND COMPARISONS: Radiographic fracture healing, complication rates, weight-bearing status, length of stay, gait impairment, and patient-reported outcomes using the Patient-Reported Outcomes Measurement Information System (PROMIS) were investigated. Multivariable regression models were employed to identify predictors of union, reoperation, discharge disposition, and postoperative complications. RESULTS: A total of 191 patients were included, with 153 (131 lateral locked plate, 22 IMN) treated with a single device construct (mean age 72 years [range 22-95], 16% male) and 38 treated with nail-plate combination constructs (mean age 70 years [range 19-94], 16% male). At one-year post-operatively, nail-plate combination versus single device constructs were associated with significantly lower rates of nonunion (0% vs 12%, p=0.03), reoperation (10% vs 26%, p=0.05), and gait impairment (26% vs 58%, p<0.01). Patients in the nail-plate combination group versus the single device group were more likely to be weight bearing as tolerated at discharge (63% vs 3%, p<0.01) and more frequently discharged home (42% vs 15%, p=0.04). CONCLUSIONS: Fixation with nail-plate combination constructs, compared to single device constructs, in distal femur fractures appeared to support immediate weight bearing and was associated with improved short- and mid-term outcomes, including reduced rates of nonunion, reoperation, and functional impairment at one year. These advantages may be especially relevant for geriatric patients and those with complex or periprosthetic fracture patterns, or with preoperative risk factors for nonunion and functional decline. LEVEL OF EVIDENCE: III.