Preface

In February 2018, my first book titled "Biomimetic Prosthetics" was published by IntechOpen. This was an edited volume with contributions from researchers all over the world on biomimetic (mimicking complex biological sensorimotor systems of human beings and animals) prosthetics. With over 2500 downloads, multiple citations and compliments from my colleagues, this was a rewarding experience. I would like to thank the authors for their valuable contributions and staff at IntechOpen in this book project. I would also like to extend my special thanks to my students from the Sensorimotor Control Laboratory at Stevens who contributed towards the introductory chapter of this book. In June 2018, I was approached by commissioning editors at IntechOpen to see if I was interested in leading another edited volume on "Prostheses". This could cover a broader category of prostheses and appeal to a wider audience. I took some time and responded favorably for the following reason. During my previous project on Biomimetic Prosthetics, I rejected several applications on prosthetics as they were not necessarily biomimetic. During that project I realized that there was a need to provide another opportunity for these other valuable contributions. This came to me in the form of this current book "Prosthesis". It has been a great learning experience and an inspiring academic journey through these book projects.

In this book, the readers will find information on various prostheses for upper limb, lower limb, retinal, and facial prostheses. These areas of research are multidisciplinary, requiring expertise in electrical engineering, mechanical engineering, biomedical engineering, material sciences, and tissue engineering. The uniqueness of the field of prostheses is in combining multiple expertise to improve technologies that can help individuals with impairments.

The introductory chapter presents the evolution of prosthesis and their applications in different domains. This chapter prepares the readers with the context, application, and importance of prosthesis.

The second chapter talks about control methods for the transhumeral prosthesis considering the task environment and object properties. Specifically, this study explores how using such information coupled with around-shoulder muscle action potentials targeted reaching positions that can be accurately and rapidly identified.

While the second chapter talks about upper limb prosthesis and control, the third chapter talks about hybrid neuroprosthesis for lower limbs. This chapter summarizes the principles of human mobility and the impact of spinal cord injury on an individual's mobility. This chapter also talks about how a hybrid prosthesis combined with functional electric stimulation and orthoses can be used to reactivate paralyzed muscles and enable function.

In the fourth chapter, residual lower limb health and possible prosthetics are discussed. Changes in residual limb properties may affect socket fit and may lead to serious injuries. This chapter presents socket systems available in the market and compares them with the elevated vacuum suspension system that could improve and provide physiological benefits to the residual limb.

In the fifth chapter, ambulatory assistive devices for individuals with injuries or disabilities in lower extremities are discussed. These devices play an important role in providing support, stability, and balance. In particular, this chapter talks about some useful guidelines in prescriptive ambulatory devices.

Switching gears to other prosthesis systems, the next two chapters talk about retinal prosthesis and facial prosthesis. In the sixth chapter, an overview is given of the Argus II retinal prosthesis system, as well as requirements, results achieved to date, challenges, and some future directions.

In the seventh chapter, using additive manufacturing, 3D color printed soft tissue facial prostheses are described. The chapter talks in detail about methods involved in assessing mechanical properties of materials, infiltrating them with silicone polymers, and testing their specifications for their potential use for facial prosthesis.

This book is a representative compilation of several types of prostheses, their importance, their challenges, and recent scientific and technological developments. I would like to thank the authors with diverse expertise for their valuable contributions. I would also like to thank IntechOpen staff especially Josip Knapic, Petra Svob, and Martina Brkljacic for their kind assistance throughout the editing process. Without their help, this book would just remain an idea. I hope that the readers will be informed and inspired from reading this book.

> **Ramana Vinjamuri and Harvey N Davis** Distinguished Assistant Professor, Director of Sensorimotor Control Laboratory, Department of Biomedical Engineering, Schaefer School of Engineering, Stevens Institute of Technology, New Jersey, USA

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**Chapter 1**

**1. Background**

Introductory Chapter: Past,

*Shanthini Madhanagopal, Martin Burns, Dingyi Pei,* 

outlined in **Table 1**. This is a summary of our findings from [8, 9].

limitations, and recent advancements will be discussed in this chapter.

Upper limb (UL) paralysis and other motor deficits are common after a stroke. About 70% of acute phase patients and 50% of chronic phase patients experience such deficits. Upper limb paralysis affects tens of thousands worldwide, and all the forms of paralysis as a whole affect millions [12]. Currently, there is no way to safely cure paralysis. Instead, upper limb paralysis patients undergo rehabilitation treatment

**2. Virtual reality rehabilitation**

and Rehabilitation

Present, and Future of Prostheses

*Rohan Mukundhan, Helen Meyerson and Ramana Vinjamuri*

A prosthesis is defined as "…a device attached to the stump of an amputated body part due to traumatic or congenital conditions…" [1]. Prostheses have evolved over the past centuries, starting with a wooden toe to the highly mechanized robotic limbs of today. The evolution of prosthesis started in the Egyptian period during which wood was used as a replacement for a missing toe, coconut shell was used as a dental implant, and various other materials were used as an alternative to different body parts. There are various types of prostheses depending on the body part being replaced. These include upper and lower limb (LL) prostheses, neural prostheses (NP), retinal prostheses, maxillofacial prostheses, and various other types. Each prosthesis is designed and assembled based on the person's physical appearance, functional needs, and affordability [2–7]. The history of lower limb prosthesis is

Amputations are estimated to occur between 300 and 500 times per day, leading to an increased usage of prostheses [10]. With increased need there are various factors which impact prosthesis usage, including whether the amputation is unilateral or bilateral, the time duration between amputation and prosthetic fitting, type of prosthesis used, physical health factors such as phantom-limb pain, and the psychological impact of amputation such as perception of symptoms, self-efficiency, balance confidence, treatment cost, and time taken to adapt to the prosthesis. The quality of life post-rehabilitation does not solely depend on the abovementioned factors but also includes functional utility and satisfaction over time. Improvements in quality of life are possible with recent innovations in design tools, materials, and different types of manufacturing, aiding in customizing prosthesis according to patient needs [11]. Novel rehabilitation methods, different types of prostheses, their
