pediatric tumor resection and recon-struction: outcomes of osteoarticular allograft fix-ation with stabilized dynamized nailing technique

Background: reconstructing large bone defects after lower limb tumor resection remains a challenge in pediatric orthopedics. while osteoarticular allografts offer a biological solution, achieving stable fixation and union is crucial to minimize complications such as fractures and nonunions. objectives: we aimed to explore a novel, stabilized, dynamized nailing technique (sdnt) to enhance outcomes in pediatric patients undergoing tumor resection and reconstruction.methods: between 2014 and 2024, 40 pediatric patients (mean±sd age: 11.85±2.93 years) with malignant bone tumors (70.73% osteosarcoma, 24.39% ewing sarcoma, 2.44% chondrosarcoma) underwent wide resection (≥2 cm margins) and reconstruction with fresh frozen osteoarticular allografts (ffoa) soaked in gentamicin. fixation was achieved using sdnt, a modified intramedullary nailing (imn) approach designed to promote union through controlled dynamization. patients were followed for a mean±sd of 33.68±20.58 months, with outcomes including union time, complications, and survival assessed via clinical and radiographic evaluations.results: the mean±sd union time was 9.71±3.05 months. complications occurred in 48.88% of patients, with delayed union (24.39%), infection (14.64%), and drop foot (4.88%) being the most common. notably, no fractures occurred except for nail bending (2.44%). survival was 70.73%, with a 29.27% mortality rate and 17.07% disease relapse. metastasis affected 29.27% of patients, primarily in the lungs (26.83%).conclusion: sdnt with osteoarticular allografts offers a promising approach for pediatric lower limb tumor reconstruction, achieving a low fracture rate and effective bone union despite a high overall complication rate. these findings suggest sdnt may improve mechanical stability compared to traditional fixation methods, warranting further investigation.