Functional outcomes of portal-matched tibial intramedullary nailing in Fraser type I floating knee injuries: a retrospective case series

Floating knee injuries are high-energy injuries with considerable functional morbidity. In Fraser type I injuries, dual intramedullary nailing permits early stabilization and mobilization. While suprapatellar nailing offers technical advantages for proximal-third tibial fractures, its role within floating knee injuries remains inadequately described. This study evaluated functional recovery following portal-matched tibial nailing in Fraser type I floating knee injuries. A retrospective case series of seven adults with Fraser type I floating knee injuries treated with dual intramedullary nailing between February 2022 and February 2026 was conducted at a tertiary care centre. Five patients with diaphyseal tibial fractures underwent infrapatellar nailing, while two with proximal-third fractures underwent suprapatellar nailing. Functional outcome was assessed using the International Knee Documentation Committee (IKDC) subjective score at 6 weeks, 6 months and 2 years. Pain, radiological union and complications were also recorded. Outcomes were analysed descriptively given the small and imbalanced subgroups. The COHORT comprised five males and two females, with a mean age of 33.6±7.2 years. Mean IKDC scores improved progressively from 61.54±2.15 to 82.42±2.46 and 86.70±1.30 at 6 weeks, 6 months and 2 years, respectively, in the infrapatellar group. Corresponding scores in the suprapatellar group were 60.30±0.85, 82.85±1.34 and 86.80±0.57. No clinically meaningful difference in functional recovery was observed. No non-union, malunion or implant failure occurred. Portal-matched tibial nailing demonstrated favourable and comparable functional recovery across diaphyseal and proximal-third fractures in Fraser type I floating knee injuries. Larger prospective studies are required to validate these findings.