PROSTHETIC AND ARTIFICIAL ORGANS SESSION: 12BME SEMESTER: 7 TH (FINAL YEAR) SUBJECT TEACHER: HIBA PERVAIZ 1

Course Outline Overview of Prosthesis with examples. Overview of Artificial Organs with examples. Limb Prosthesis-Functional requirements, Design criteria. Joint Prosthesis- Joint pathologies, Important artificial joints. Tissue reaction to implants, Types & failures of implanted joints. Artificial Heart Valves- Cardiac anatomy & pathophysiology. Prosthetic Heart valves, Evaluation of Prosthetic valves. Sessional Test-I Artificial Heart- Cardiac Anatomy & pathophysiology. Heart assist technology, Evaluation of Blood pumps. Cardiac pacemakers, Cardiac electrophysiology & pacemaker implantation. Artificial Kidney- Nephron & mass transfer. Dialysis procedure & dialysis system. Artificial Lungs. Artificial Pancreas. Artificial Blood. Materials used for artificial organs. Artificial Organ design approaches. Manufacturing Issues. Sessional Test-II 2

PROSTHESIS LECT # 01 3

What Are Prosthetics? Prosthetics are artificial limbs or body parts, that replace missing or malfunctioning body parts Most common prosthesis are the leg and arm, and more recently also heart valves

Prosthetic Leg & Arm

What Are Prosthetics? In a broader sense, ‘prosthesis’ is the name for any artifact that is used to restore bodily functions, OR it is an artificial device used to replace a missing body part such as a limb, tooth, eye or heart valve. ‘prosthetics’ is the name of a field concerned with the development and fitting of artificial body parts. Prostheses in this broader sense are an important focus of the relatively new field of bioengineering, or biomedical engineering, which is a branch of engineering concerned with the application of engineering techniques to medicine and the biomedical sciences. 6

Prosthetics, Orthotics, Prosthodontics In a narrow sense, prosthetics is a branch of medicine, specifically of surgery, concerned with the replacement of missing body parts (upper and lower limbs, and parts thereof) after amputation. It is related to orthotics, which is a branch of medicine that deals with the support of weak or ineffective joints or muscles using supportive braces and splints. In dentistry, prosthetics or prosthodontics is that branch concerned with the replacement of missing teeth and other oral structures. In this narrow sense, a prosthesis is a replacement artificial limb or tooth. 7

8 A United States Army soldier plays table football with two prosthetic arms Jon Comer, professional skateboarder with a prosthetic leg.

The Beginning Around 1500 B.C. was the time when “prosthetics” were “engineered” Were not functional Only purpose was to help with movement Were generally made of wood

The Push Towards Modern Prosthetics In the mid 1800s, Sir James Syme discovered a way to amputate at the thigh This meant that there was a possibility of walking again Both World Wars were key in the developmental progress of prosthetics

Design Breakthroughs In the early 1800s, James Potts designed the first wooden functional prosthetic foot, which was controlled by tendons from the knee to the foot In the mid 1900s, prosthetics now had a endo- skeletal design instead of a exo-skeletal This allowed the hard shell-like exterior to be replaced with a foam cover, so the weight and force was applied to the ‘core’ of the prosthetic rather than the exterior

Evolution

Causes the most common causes of amputation are: Disease (70%) Trauma (22%) Congenital or Birth Defects (4%) Tumors (4%) Diseases that can cause amputation are varied, but the most common ones are vascular disease and diabetes. Vascular disease limits the circulation to the extremities. Diabetes, which affects blood sugar, can decrease the body's ability to heal itself. Trauma resulting in amputation is most frequently related to motor vehicle accidents and industrial accidents. Congenital malformation or birth defects can result in either the person having no limb or a very short limb that is treated as an amputation, for which a prosthetic device is made. Tumors of the bone, called osteosarcoma, can sometimes be treated by amputation of the limb. 13

Bioengineering and Prosthetics Several areas in bioengineering have special relevance to prosthetics. Rehabilitation engineering is an area concerned with the application of engineering science to restructure the handicaps of individuals with disabilities. It includes prosthetics and orthotics but also addresses other disabilities, specifically sensory and speech impairments. It does not address functional impairments in internal organs, however. 14

Tissue engineering, which involves the repair or replacement of organic cells, tissues, or organs with laboratory-grown biological substitutes; biomaterials engineering, which aims at the development of synthetic or natural materials that can replace or augment tissues, organs or body functions; 15

Biomechanics, which studies the human musculoskeletal system and its mechanical aspects and includes artificial limb and joint design; Cardiovascular engineering, which studies the cardiovascular and blood system and develops techniques and systems for diagnosis, intervention, therapy and replacement. neural engineering, which studies the nervous system and develops means to repair or replace damaged and non-functioning nerves and sensory systems. 16

Neuro-prosthetics is a rapidly growing subfield of neural engineering that aims to develop devices or systems that communicate with nerves to restore functionality of the nervous system. 17

Development in Prosthetics Currently, a large number of human biological functions can already be restored or improved with the aid of prostheses. Implants and devices that were in use includes:  artificial limbs, including robotic ones and ones with sensory feedback to the body;  artificial muscles made of polymer;  artificial skin used to promote healing;  artificial joints, hips and vertebrae;  artificial bone used to help heal fractures and replace diseased bone;  dental implants and false teeth;  silicone or plastic implants to build bony structures of the face;  speech synthesizers and artificial larynxes to restore speech; 18

 vessels and urological systems;  artificial blood (experimental);  retinal implants (experimental), intraocular lenses and artificial corneas to restore vision;  Cochlear implants that replace the inner ear and involve a microphone, speech processor and wiring to the nervous system;  artificial nerves (experimental);  electrodes implanted in the brain to control seizures or tremor;  breast implants;  cardiac pacemakers, defibrillators, artificial heart valves and heart-assist pumps; 19

 artificial hearts;  implanted chips to locate persons or to regulate devices in “intelligent environments”;  implanted drug delivery systems (experimental);  Research is underway on bioartificial livers, kidneys, pancreases, lungs, and other organs, as well as on more advanced neural prostheses to restore functions of the brain and nervous system. 20