INTERNSHIP REPORT

TOTAL KNEE REPLACEMENT

SUBMITED BY: DOAN VIET SANG (21203090)

Faculty Advisor: Dr. Pham Huy Hoang.

Guided by: Dr. Thunyaseth Sethaput.

THAILAND, AUGUST 2016

INTERNSHIP REPORT

Total Knee Replacement.

by

Doan Viet Sang

Eng.B Mechanical Engineering

Ho Chi Minh City University of Technology

Submitted to Department of Manufacturing Engineering

In fulfillment of Requirements of Graduated Internship for

Degree of Bachelor of Mechanical Engineering

at the

Ho Chi Minh City University of Technology

Signature of Author…………………….. Doan Viet Sang Faculty of Mechanical of Engineering

1st August 2016

Certified by ……………………………….. Dr. Pham Huy Hoang Associate Professor of Mechanical Engineering

Thesis Supervisor

Accepted by ………………………………

Preface

I have completed my 4th year in bachelor degree of mechanical Engineering at Ho Chi Minh

City University of Technology. This internship is the final internship and I am going to do my

thesis in next semester. I choose to do internship abroad because I want to experience myself

in international research environment. In addition, I want to develop new sets of skills. One

of my goal is improving English skill to preparation of studying abroad in the future.

Sirinhorn International Institute of Technology (SIIT) is a reputation research place in Thailand,

which is supported by Nippon Keidanren, Federation of Thai Industries and Thammasat

University. SIIT provides courses would be taught in English by highly qualified faculty

members with doctoral degrees.

In this internship report, I will describe my experiences during my internship period. The

internship contains overview of SIIT, my project topic “total knee replacement”.

For this opportunity, I thank:

Dr. Thunyaseth Sethaput, who is my advisor at Sirindhorn International Institute of

Technology (SIIT), Thammasat University. I want to thank him for giving me opportunity to

follow my internship at SIIT. He had the kindness to accept me in his laboratory and guide me

throw my internship by giving advices, feedback and tips.

ASS, Prof Pham Huy Hoang, who is my advisor at Ho Chi Minh City University of Technology

(HCMUT). He supported to complete the application for my internship at SIIT, Thailand.

Mr. Amila Hemantha, who is currently doing master course at SIIT. He help me to adapt the

life in Thailand at the beginning of my internship.

Besides my internship, I really enjoy my stay in Bangkok, Thailand. It was a good time with

unforgettable experience.

CONTENTS

1. General Information of SIIT. ………..………..………..………..………..………..………..……….……… 1 2. Research Topic. ………..………..………..………..………..………..………..………..………..………..……….. 2 2.1. Introduction. ………..………..………..………..………..………..………..………..………..………..………. 2 2.1.1. Medical Background. ………..………..………..………..………..………..………..………..……….. 2 2.1.2. Total Knee Replacement. ………..………..………..………..………..………..………..…………… 3 2.2. Custom-made Total Knee Replacement ………..………..………..………..………..………..… 4 2.2.1. Patient Data. ………..………..………..………..………..………..………..………..………..…………… 4 2.2.2. Creating 3D model of femur part by using CAD software ………..………..……….. 6 2.2.3. Rapid Prototype of Femur Part. ………..………..………..………..………..………..………….. 6

FIGURES

Figure 1: Sirindhorn International Institute of Technology ………..………..………..………..………..… 1 Figure 2: Knee Components ………..………..………..………..………..………..………..………..………..……….. 2 Figure 3: Knee caused by Osteoarthritis………..………..………..………..………..………..………..……….. 2 Figure 4: Total Knee Replacement ………..………..………..………..………..………..………..………..……… 3 Figure 5: Patient Data from Thammasat Hospital………..………..………..………..………..………..…… 4 Figure 6: CT scan Data mistakes………..………..………..………..………..………..………..………..………..… 5 Figure 7: CAD model transferred from CT scan by Mimics………..………..………..………..………..… 5 Figure 8: Using Loft feature of SolidWorks ………..………..………..………..………..………..………..…… 6 Figure 9: 3D Model by SolidWorks ………..………..………..………..………..………..………..………..……… 6 Figure 10: How FDM 3D printing works ………..………..………..………..………..………..………..……….. 6 Figure 11: Properties Adjustment ……………………………………………………………………………………… 7 Figure 12: Toolpaths Generation ………………………………………………………………………………………… 7

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1. General Information of SIIT.

Sirindhorn International Institute of Technology (Thai: สถาบนัเทคโนโลยนีานาชาตสิรินิธร) is established

in 1992 within Thammasat University. SIIT is known as a premier research university in

Thailand which has many fields such as science, technology and engineering, as well as

management programs. All are international program with English.

SIIT has 5 schools and 1 department:

School of Bio-Chemical Engineering and Technology

hosts chemical engineering and environmental technology programs

School of Civil Engineering and Technology

hosts civil engineering and infrastructure planning programs

School of Information, Computer and Communication Technology

hosts information technology, computer science, and Electronics and communication

engineering programs

School of Management Technology

hosts management technology and engineering management programs

School of Manufacturing Systems and Mechanical Engineering

hosts mechanical engineering and industrial engineering programs

Department of Common and Graduate Studies

Figure 1: Sirindhorn International Institute of Technology

In the Academic year 2003, SIIT showed the highest number of research publications of any

academic division in the university. In 2007, Thai Research Fund put SIIT in the top of all

Engineering Faculty in Kingdoms.

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2. Research Topic.

2.1. Introduction.

2.1.1. Medical Background.

Knee

Knee is one of complex joints in human

body. The main function of knee is

connecting Femur bone and Tibia

bone. Besides two major bones, knee

includes Fibula which runs alongside

the Femur bone and Patella (knee cap)

which makes knee joint.

Tendons connect the knee bones to

the leg muscles that move the knee

joint. Ligaments join the knee bones

and remain stability to the knee:

The anterior cruciate ligament

prevents the femur from sliding

backward on the tibia (or the tibia sliding forward on the femur).

The posterior cruciate ligament prevents the femur from sliding forward on the tibia

(or the tibia from sliding backward on the femur).

The medial and lateral collateral ligaments prevent the femur from sliding side to side.

Osteoarthritis

Osteoarthritis is the most common form of arthritis

as well as the most popular disease of knee, which

affects millions of people worldwide. It occurs when

the protective cartilage on the ends of your bones

wears down over time.

Country impact

United Kingdom

In England and Wales between 1.3 and 1.75 million

people have symptomatic OA. In 2000 more than

80,000 hip or knee replacements were performed at

a cost of £405 million.

As a cause of disability (such as walking and climbing

stairs) in the elderly OA is second to cardiovascular

disease.

Altogether 10% to 15% of adults over 60 have some degree of OA.

Figure 2: Knee Components

Figure 3: Knee caused by Osteoarthritis

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Germany

Four million people out of 82 million people (4.8% of population) suffer from some form of

autoimmune conditions affecting joints.

Canada

The direct and indirect costs of arthritis in Canada equates to approximately $18 billion per

year.

Over four million Canadians out of 31,014,000 people have arthritis.

Currently there are approximately 270 rheumatologists in Canada; however, 150 of them are

close to retirement leaving 120 rheumatologists to care for 4 million suffering arthritis

patients.

There are approximately 37,000 hip and knee replacement surgeries every year in Canada.

Japan

Population of 127 million people.

17% of population is over 65 (this percentage is expected to grow by 25% in the next three

decades).

5% of the population has some form of arthritis.

2.1.2. Total Knee Replacement.

Total Knee Replacement is a surgical

procedure to replace the damage surfaces

of the knee joint to relieve pain and

disability. It is used for osteoarthritis, and

also for other knee diseases such

as rheumatoid arthritis and psoriatic arthritis.

Total Knee Replacement has a long history

development and it is becoming common

as the population of the world. Artificial

Knee Replacement can be classified in two

basic types: cemented prosthesis and non-

cemented prosthesis. Cemented

prosthesis consists a type of epoxy cement

for fixation, whereas non-cemented

prosthesis has a smooth surface intended

for bone to grow into and attach the

prosthesis to the bone. In addition, Total

Knee Placement can be performed as partial or full knee replacement.

Figure 4: Total Knee Replacement

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2.2. Custom-made Total Knee Replacement

Custom-made Total Knee Replacement is a form of Total Knee Replacement. Comparing to

Standard Total Knee Replacement, Custom-made Total Knee Replacement helps patients

avoid removing undamaged part and less painful.

In this Internship, I worked on femur part of Custom-made Total Knee Replacement which is

3 main works:

Collecting and Processing Patient Data.

Design Femur Part of Total Knee Replacement based real data, supported by CAD

Software.

Using Rapid Prototype to create 3D model.

2.2.1. Patient Data.

Patient Data is collected by the computer tomography (CT) Scanner and processed by Mimics

software. This 60 years old patient data is provided by Thammasat Hospital (TH), Thammast

University Thailand. According to TH, this patient has suffered from Osteoarthritis for 3 years

and It has made serious consequences by limitation of knee movements. Beside other methods, Total

Knee Replacement Surgery is a consideration treatment for this case.

There are many unnecessary parts and holes from rough data. The reasons of this problem is the

accuracy of CT scan machine. Mimics technic is applied to get patients data accurately and fill up the

holes

Figure 5: Patient Data from Thammasat Hospital

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By using Mimics, CT scan images can be transfer into 3D model.

Figure 6: CT scan Data mistakes

Figure 7: CAD model transferred from CT scan by Mimics

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2.2.2. Creating 3D model of femur part by using CAD software.

There are numerous methods to create

femur part of Total Knee Replacement but

in this internship, I decided to use loft

feature by SolidWorks, including draw

definition line following 3D model from CT

scan.

The revolution of loft feature is 1 mm which

is the distance of spline lines. The spline

guide line will be generated automatically

by the software. The distance could be

smaller by drawing more spline definition

lines but the results I got is not better so 1

mm is the best option.

After recreation of Knee model, I complete the model

by cutting assembly surfaces. According to

recommendation of Thammasat hospital doctor, the

assembly surface must be less painful for patient as

well as avoiding removing undamaged part.

2.2.3. Rapid Prototype of Femur Part.

Principles of FDM (Fused Deposition Modeling)

Figure 8: Using Loft feature of SolidWorks

Figure 9: 3D Model by SolidWorks

Figure 10: How FDM 3D printing works

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Using Catalyst EX to control FDM 3D Printer

Adjustment of Properties

Layer resolution: The thickness of each layer.

Model interior: Inside Structure of Model.

Support fill: Type of Support Fill

Number of copies: Number of model printing out.

Generating toolpaths

Figure 11: Properties Adjustment

Figure 12: Toolpaths Generation