FUNCTIONAL AND RADIOLOGICAL OUTCOMES OF SUPRAPATELLAR INTRAMEDULLARY INTERLOCKING NAILING IN SEGMENTAL AND EXTRA-ARTICULAR PROXIMAL TIBIAL FRACTURES: A PROSPECTIVE STUDY

Abstract

Background: Conventional infrapatellar intramedullary nailing of proximal tibial fractures is technically demanding and is associated with characteristic procurvatum and valgus malalignment as well as a high incidence of anterior knee pain. The suprapatellar, semi-extended approach has been proposed to overcome these limitations. Prospective data on its use in segmental and extra-articular proximal tibial fractures as a combined cohort, particularly from Indian tertiary-care settings, remain limited. Materials and Methods: This prospective observational study included 20 adults with segmental or extra-articular (AO/OTA type 41-A) proximal tibial fractures treated with suprapatellar intramedullary interlocking nailing at a tertiary teaching hospital between 2023 and 2026. The primary outcomes were time to radiological union (Radiographic Union Scale for Tibial fractures, RUST), postoperative coronal and sagittal alignment, and functional recovery measured by the Lysholm Knee Score at 12 months. Secondary outcomes included operative time, hospital stay, time to full weight-bearing, knee range of motion, and anterior knee pain (Visual Analogue Scale, VAS). Extra-articular and segmental fracture groups were compared using appropriate parametric and non-parametric tests, with p < 0.05 considered significant. Results: The mean age was 38.55 ± 10.78 years; 16 patients (80%) were male and road traffic accidents accounted for 65% of injuries. The overall union rate at 12 months was 100% (mean RUST 10.35 ± 0.88). All patients (100%) achieved acceptable alignment (≤ 5°) in both planes (mean coronal 2.75 ± 1.37°, sagittal 2.80 ± 1.36°). The mean Lysholm score was 87.25 ± 8.42, with 80% of patients rated excellent or good. Compared with extra-articular fractures, segmental fractures had significantly longer time to union (22.00 ± 1.58 vs 15.67 ± 3.22 weeks; p = 0.003) and time to full weight-bearing (13.00 ± 0.71 vs 9.07 ± 2.12 weeks; p = 0.006). Both union time and Lysholm score differed significantly across AO subtypes (p < 0.001). Anterior knee pain was generally mild (mean VAS 1.50 ± 1.32). Conclusion: Suprapatellar intramedullary interlocking nailing is an effective and reliable technique for segmental and extra-articular proximal tibial fractures, achieving excellent union and alignment with satisfactory functional recovery and low anterior knee pain. Fracture complexity significantly influences healing time and functional outcome.