A preoperative planning method for long tubular bone osteosynthesis

Abstract

Objectives the development of a preoperative planning method for long tubular bone osteosynthesis using the contralateral healthy bone.
 Material and methods.To justify the usage of the opposite limbs intact segment model in order to reconstruct the damaged one, their matching in shape and size was analyzed. We built three-dimensional models of the right and left segments of the upper limbs of 20 people and compared them using the Hausdorff distance calculation algorithm. For treatment of a 24-year-old patient with a closed humerus fracture, an individual stereolithographic surgical template with fracture lines was created with the help of computed tomography data of the healthy humerus bone processed by AUTOPLAN EXPERT software. This template was used for pre-bending the plate for osteosynthesis. The plate positioning on the template defined the surgical approach, taking into account the anatomical structures located in the projection of the fracture line and the plate. The technique of "reverse bone reposition" on the prepared plate was applied.
 Results.With the help of the created 3D models we revealed the size differences of the symmetrical segments of upper limbs. The greatest difference in the limits was registered in the area of the epiphyses (heads of the humeri) up to 6.8 mm, and the smallest throughout the entire diaphysis, less than 1.5 mm. Due to preoperative planning there were no intraoperative and postoperative complications, the installation of the plate and osteosynthesis was convenient. The fracture consolidation took place in 3 months.
 Conclusion.The proposed method has a number of advantages. It is possible to make a stereolithographic template even for a seriously damaged bone with a copied fracture line. This allows the surgeon to plan the details of osteosynthesis, to model the plate according to the template, to determine the required length and shape of the surgical approach, thus reducing the surgical risks and injury for the patient.