Desenvolvimento de um procedimento para a fabricação de órteses não articuladas de tornozelo e pé por manufatura aditiva

Abstract

Lower limb orthoses are assistive devices commonly prescribed by physiotherapists to assist in the treatment of patients with motor deficiency or with deformities in the lower limbs. They are intended to improve limb function and prevent progression of deformity. They can be purchased in standard sizes or manufactured specifically for the user, i. e., customized. Traditionally, these customized orthoses are manufactured by a process that often does not result in a comfortable or attractive orthosis for the patient, discouraging the use. Combining 3D Scanning Technologies to Additive Manufacturing (AM), also known as 3D printing, it is possible to manufacture anatomical products. In this way, these technologies can contribute to the manufacture of anatomical ankle-foot orthoses (AFO) and, also customized according to the user's wishes. The present study aims to develop a procedure for the manufacture of nonarticulated ankle-foot orthoses by Additive Manufacturing. The research was divided into three main phases: bibliographic review, process development, based on the bibliographic review; the application and evaluation of products manufactured through the developed procedure. The bibliographic review was performed to mitigate the existing knowledge about manufacturing process for orthoses by AM, as well for the AFO and foot orthoses (FO) already produced by Additive Manufacturing. A method of developing customized orthoses for upper limbs by Additive Manufacturing has been adapted for application to lower limb orthoses. The steps involved in the process of developing non-articulated ankle-foot orthoses by Additive Manufacturing were acquisition of geometry; 3D scanning; mesh treatment; 3D modeling; process planning; 3D printing; post-processing; delivery and evaluation. As the acquisition of modern equipment is still a limitation considering the Brazilian reality, it was applied only lowcost technologies such as the 3D-scanning from Kinect 360 sensor and low-cost Anet® A8 DIY 3D printer, based on the principle of material extrusion. The developed method was applied in the development of AFO orthoses for four children from one to four years, attended at Centro Vitória in Curitiba / PR. As results of the study, the procedure for manufacturing non-articulated ankle-foot orthoses by Additive Manufacturing was obtained, as were four pairs of non-articulated ankle and foot orthoses, one pair for each child. Orthoses made of TPU (thermoplastic polyurethane) by 3D printing were approved by physiotherapists on static evaluations and resisted efforts during physical therapy. A satisfaction assessment was performed by obtaining the opinion of the caregivers and physiotherapists through the B-QUEST questionnaire and a complementary questionnaire regarding their satisfaction with the conventional orthosis as well as the 3D printed orthosis. It was possible to perceive that the satisfaction was greater for both the caregivers and the physiotherapists for the orthoses manufactured by 3D printing, and for the latter one the results presented for 3D printed orthoses were on average 18% higher than for traditional orthoses. The maximum time involved in the manufacture of each orthosis was two weeks and the cost of the materials of each orthosis was less than R$50 (about US$12,50). With the evaluation of the orthoses produced it can be affirmed that the developed procedure was proper, reaching the objective of the research.