Accurate Entry Point for Tibial Nailing with SIGN Nail in Asians: A Cadaveric Study

Abstract

Background: Tibial nailing is a standard treatment of tibial fracture. Placing the nail in the wrong position will result in poor fracture alignment and potentially damage to cortical bone. But the exactly entry point of this technique in Thai people has never been studied. In Chiang Mai University hospital, a tibial SIGN nail is commonly used in tibial shaft fracture. Objective: To identify the accurate entry point for tibial nailing with tibial SIGN nail, defined as the point which will provide adequate fracture alignment. Design: Cadaveric study Methods: Twelve cadavers with attached knee joints underwent tibial nailing with tibial SIGN nails. After placement of the nail, the specimens underwent osteotomies at the level of 10 centimeters distal to the articular surface. Multiple entry points were tested to determine fracture alignment. Medial?lateral and anterior?posterior displacements from plain radiography were recorded for these various points of entry. Results: In coronal plane, the entry point at the sixty percent from medial edge of tibial plateau was identified as minimizing the medial-lateral displacement of the tibial shaft following fracture. In sagittal plane, the entry point of 20mm posterior to the tibial tubercle resulted in the least anterior-posterior displacement. Conclusion: When tibial nailing with tibial SIGN nail was used, the entry point of 20 mm posterior to the tibial tubercle and sixty percent of the total distance from medial tibial plateau provided the accurate balance of fracture reduction.