Advances in Orthotic and Prosthetic Manufacturing: A Technology Review

Abstract

In this work, the recent advances for rapid prototyping in the orthoprosthetic industry are presented. Specifically, the manufacturing process of orthoprosthetic aids are analysed, as thier use is widely extended in orthopedic surgery. These devices are devoted to either correct posture or movement (orthosis) or to substitute a body segment (prosthesis) while maintaining functionality. The manufacturing process is traditionally mainly hand-crafted: The subject's morphology is taken by means of plaster molds, and the manufacture is performed individually, by adjusting the prototype over the subject. This industry has incorporated computer aided design (CAD), computed aided engineering (CAE) and computed aided manufacturing (CAM) tools; however, the true revolution is the result of the application of rapid prototyping technologies (RPT). Techniques such as fused deposition modelling (FDM), selective laser sintering (SLS), laminated object manufacturing (LOM), and 3D printing (3DP) are some examples of the available methodologies in the manufacturing industry that, step by step, are being included in the rehabilitation engineering market-an engineering field with growth and prospects in the coming years. In this work we analyse different methodologies for additive manufacturing along with the principal methods for collecting 3D body shapes and their application in the manufacturing of functional devices for rehabilitation purposes such as splints, ankle-foot orthoses, or arm prostheses.

Keywords: additive manufacturing; fused deposition modeling; laminated object manufacturing; orthoses; prostheses; rapid prototyping; selective laser sintering.

Figure 1

Examples of 3D printed orthotics (a) Forearm static fixation (courtesy of Fitzpatrick et al. [21]). (b) Cyborg beast hand prosthesis—a low-cost 3D-printed prosthetic hand for children licensed under the CC-BY-NC license (courtesy of Zuniga et al. [19]). (c) Spinal brace (courtesy of Andiamo company [22]). (d) Ankle-foot orthosis (courtesy of Andiamo company [22]).

Figure 2

Phases of the manufacturing process of custom-fit orthotic devices. (A) Rapid prototyping techniques (RPT) methodology (courtesy of J. Barrios-Muriel). (B) Traditional methodology (courtesy of Mavroidis et al. [26] under CC-BY License.) Computer aided design (CAD)-computed aided engineering (CAE), computed tomography (CT).

Figure 3

Comparison of the proposed schemes dor rapid prototyping. (a) Fused deposition modeling (FDM). (b) Selective laser sintering (SLS). (c) 3DP. Image adapted from Wang et al. [74] with permission of Elsevier Ltd.