Abstract
INTRODUCTION: Distal femur fractures (DFF) in older adults carry morbidity and mortality approaching hip-fracture levels. Single lateral plate (SLP) fixation is the traditionally used modality, yet healing problems have shifted focus from implant choice to construct mechanics. We examined whether screw density (cortical engagement) relates to early outcomes after SLP. MATERIALS AND METHODS: Single-centre retrospective cohort of patients ≥65 years with DFF treated by SLP over 10 years. Primary exposure was cortical purchase (proximal and distal cortices); adjuncts of proximal/distal wires were recorded. Primary outcome was unplanned return to theatre; secondary outcomes were length of stay (LOS), time to full weight bearing (FWB; first documented WBAT/FWB), and mortality. Analyses used non-parametric group comparisons and exploratory correlations. RESULTS: We analysed 111 patients (mean age 82.1 ± 8.4; 82.0% women): 55.0% native and 33.3% periprosthetic fractures. Mean proximal and distal cortex counts were 9.09 ± 3.47 and 7.58 ± 2.58, respectively. Mean time to theatre was 4.05 ± 11.57 days; 60.0% were operated within 48 h. Mean LOS was 22.0 ± 19.7 days. FWB time was available in 81/111 (73.0%): overall median 180 days (IQR 14-180), with oldest patients often weight bearing earlier. Complications occurred in 8/110 (7.3%); unplanned returns in 6/111 (5.4%). Return to theatre was associated with higher proximal cortex count and distal wire use; proximal wire use correlated with longer LOS. Mortality occurred in 64/111 (57.7%) overall, rising from 28.6% in 65-74-year-olds to 77.3% in those aged 85-98 years. CONCLUSIONS: In elderly DFF treated with SLP, denser fixation did not correspond to better early outcomes; greater proximal cortical purchase and adjunct wiring tracked with reoperation and longer LOS. These findings support a more thoughtful approach: use longer plates with carefully chosen screws, reserve very dense or augmented constructs for clearly unstable or severely osteoporotic fractures, and plan fixation with early mobilisation in mind from the start. LEVEL OF EVIDENCE: III (retrospective cohort).