Customized Foot Orthosis Development by 3D Reconstruction of the CT Images

Sathish Kumar Paul, Sudesh Sivarasu, Lazar Mathew

Biomedical Engineering Division, SBST, VIT University, India.
Biomedical Engineering Division, University of Cape Town, South Africa ^PSG Tech, Coimbatore, India.

DOI: 10.4236/eng.2012.410088                

Abstract

Clinicians can provide a means to better distribute the pressure around the foot, and can also correct the biomechanics of the foot by using a customized shoe insole. If detected early enough, orthopedic insoles can correct or prevent further complications. In this study the 3 Dimensional (D) model of the foot was used to fabricate a customized orthosis. The Computed Tomography (CT) images of patient’s foot having no muscle weakness and joint restriction were acquired. The gray intensities corresponding to the bones of the foot from the CT images were 3 dimensionally reconstructed. The 3D model of the foot was then imported into the CAD Software. Boolean operations were carried out in between the 3D foot model and a solid rectangular surface to create a customized foot orthosis. The exact contours and shape of the subject’s foot was acquired using the computerized method of fabricating an orthosis. The novel idea described in this study support, automating the process of designing a customized orthosis with the impression got from the 3 dimensionally modeled feet, thereby reducing the modeling time considerably. The simple technique used in this process will help in giving comfort and stability to the patient’s feet while walking.

Keywords

Customized Orthosis; 3 Dimensional Foot Model; Plantar Pressure

Conflicts of Interest

The authors declare no conflicts of interest.

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