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

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

Ankle–foot orthosis design between the tradition and the computerized perspectives

“…This research has attracted the attention of many studies conducted on traditionally designed models, which are numerically obtained using optical scanning techniques. 18,19 However, these numerical designs were not accurate enough and were not adjustable prior to manufacturing.…”

Finite element model–based evaluation of tissue stress variations to fabricate corrective orthosis in feet with neutral subtalar joint

“…The fabrication of customized orthoses using the same 3D foot model has helped reduce the tissue stress caused by either STJ supination or pronation. 17…”

Estimation of foot pressure from human footprint depths using 3D scanner

“…By the combination of the traditional foot printing and the AutoCAD file we can subtract the unwanted edges and surface from the AutoCAD solid model. This method known as a Boolean operation which those facility available on AutoCAD [28], but because the traditional printing is not a digital format equalization shapes done manually. Figure 6 shows lateral foot plantar from AutoCAD before and after trimmed.…”

“…In this paper foot pressure average was found from GRF divided by the foot area contact, while GRF is equal to body weight (BW, equal BM cross gravitational acceleration g) subjects. From footprint measurements it was also possible to estimate subject's BH and BM applying Krishan equation [20,28] using as input data FW, as the following.…”