Design And Modelling Of Consistently Fitting Orthopedic Casts

3D printing,known as a new digital manufacturing technology,is increasingly widely used in various fields,such as industrial design,automobile,aviation,medical industry,jewelry design etc.It can use a variety of materials,such as plastic,metal powder,nylon,etc.to fabricate physical objects via layer by layer printing.The distinct merits of 3D printing are material saving and personalized customization compared to traditional technology.3D printing technology has been widely concerned by the medical community.At present,the main applications of 3D printing in the medical field include the manufacture of orthopedic casts,medical models,medical implants,medical scaffolds,human organs,and other medical products.This paper focuses on the application of 3D printing in the field of orthopedic casts,which encase portions of the human body to immobilize injured bones for rehabilitation.Current attempts on the geometric modelling of customized casts have not taken the swelling of the patients' broken extremities into account that causes a gradual deformation during the healing process.Thus,the shape of the injured body parts is not constant during wearing a cast,but may change along with a decreasing swelling.In this paper,we propose a framework for generating 3D printed personal casts that consistently fit and adapt to such deformations and allow to use a single cast throughout the whole healing process.The cast consists of two layers,an outer rigid layer,which provides enough strength and protection of the body parts and an underlying flexible layer that offers adaptability to the deformations.Both layers can be fabricated with standard 3D printers and easily be assembled around the injured body parts.We show some 3D printed results and demonstrate the effectiveness of our approach.