King Saud University College of Engineering Industrial Engineering Department Custom-Made Artificial Knee By Abdullah AlNuiam Supervised By Prof. Saied Darwish

Outline 1)Introduction 2)Objective 3)Artificial Knee joint 4)Biomaterial 5)Mastercam 6)CNC Machine 7)G-codes 8)Conclusions King Saud University Industrial Engineering Department

Introduction: Biomedical engineers have long been working on solutions to design a better replacement joints to improve the lives of the thousands of patients every year The design, manufacture and placement of these artificial joints require a high degree of skill and a thorough knowledge of physics, biology and chemistry Some examples: Artificial hips, knees and other joints. Ultrasound, magnetic resonance imager (MRI) and other medical imaging techniques. King Saud University Industrial Engineering Department

Types of joints Ball and socket joints Gliding joints Hinge joints Saddle joints King Saud University Industrial Engineering Department

Knee Joint The knee is the largest joint in the body Normal knee function is needed to perform routine everyday activities The most common reason for having a knee replaced is osteoarthritis.

Problem definition This project aims to manufacture a custom made knee joint locally using MasterCAM to design and CNC machine to manufacture. King Saud University Industrial Engineering Department

Normal Knee: The knee is the largest joint in the body Normal knee function is needed to perform routine everyday activities It consists of: Femur: which rotate the upper end of the shin bone (tibia) Tibia: which is the shin bone Patella (knee cap): which slides in a groove on the end of the femur. King Saud University Industrial Engineering Department

What Is a Knee Replacement? The most common reason for having a knee replaced is osteoarthritis. Knee replacement, is a surgical procedure in which the diseased parts of the knee joint are removed and replaced with new artificial parts. The goals of knee replacement surgery include increasing mobility, improving the function of the knee joint, and relieving pain. King Saud University Industrial Engineering Department

Surgical Considerations: When choosing an implant, the surgeon will consider many factors, including the patient's: Age Weight Gender Anatomy Activity level Medical history General health King Saud University Industrial Engineering Department

How Are Knee Problems Diagnosed Diagnostic tests depend on the findings of the medical history and physical exam, such as: X-ray Computerized axial tomography (CAT) scan Bone scan (radionuclide scanning) Magnetic resonance imaging (MRI) Biopsy Those tests are needed in designing “custom-made” knee joint; they show angles and sizes needed to produce a replacement knee that matches this human's body structure. King Saud University Industrial Engineering Department

Injuries 1.Osteoarthritis (OA) 2.Rheumatoid 3.Avascular Necrosis 4.Malalignment of Knee Joint King Saud University Industrial Engineering Department

Project Objective: The custom-made is the only solution for tumor patients. Hospitals need to convert the x-ray into solid models that can be manufactured. The Objective is to test the visibility of manufacturing a custom-made artificial knee joint locally. This is to develop a special design to suit each patient with the minimum possible time and minimum cost King Saud University Industrial Engineering Department

Knee Replacement The complexity of the knee joint has presented special challenges in the design and insertion of an artificial joint. The knee needs to allow movement from zero (straight) to 90 degrees at least. King Saud University Industrial Engineering Department

Components of Artificial Knee Femur (top) Tibia (bottom) Polyethylene (in between) King Saud University Industrial Engineering Department

Types of Knee Replacements Depending on the degree of mechanical stability provided by the design of the artificial knee, there are three basic categories of knee replacement: Non- constrained Semi- Constrained Unicondylar King Saud University Industrial Engineering Department

Progresses in Knee Replacement Technology has led to the development of materials used. Major advancements in knee replacement have greatly improved the outcome of the surgery Artificial joint replacement for arthritis of the knee is one of the most successful surgeries of the last century 95% of people are able to begin walking the day following surgery and pain relief is achieved. King Saud University Industrial Engineering Department

Advantages of Knee Replacement This operation produces very effective and long lasting relief from joint pain It gives a joint which functions normally The recovery period from the operation is very short The patient is able to walk from the 2 nd or the 3 rd day after the operation. The patient regains a normal lifestyle and mobility with significant improvement in quality of life King Saud University Industrial Engineering Department

Biomaterial Biomaterial are materials used for surgical or dental instruments and for external prostheses. A biomaterial placed within the interior of the body must be biocompatible. It should possess adequate physical and mechanical properties to serve as replacement of body tissues It should be amenable to be formed into different shapes, have relatively low cost, and be readily available King Saud University Industrial Engineering Department

Biomaterial The primary materials used in Total Knee System implant components include cobalt chromium molybdenum alloy (Co-Cr-Mo) Cross Section of CO-Cr-Mo formal cross sections of tibia base plate King Saud University Industrial Engineering Department

Types of Wear Abrasive Wear Adhesive Wear Fatigue Wear Third Body Wear King Saud University Industrial Engineering Department

Role of Industrial Engineer Gather information about joint/bones dimensions using x-rays to come up with suitable knee replacement sizes Develop models for patients come up with an appropriate combination of cement thickness, offset distance and femoral head size that will accommodate the patient's size. Implementing CAD/CAM and extracting CNC codes to manufacture the appropriate knee replacement for Saudi patients Predict the durability of the replacement by modeling the progress of the wear behavior of replaced components King Saud University Industrial Engineering Department

Mastercam MasterCAM is a commercial Computer Aided Manufacturing software package includes a CAD environment, a geometry-to-G-code translator, and a G-code simulator. MasterCAM provides full 2D and 3D design capability for drawing mechanical parts, and creates output code for programming CNC King Saud University Industrial Engineering Department

Advantages of MasterCAM 1)Mastercam can build work-holding fixtures, complex 3D form fixtures, and to build assemblies. 2)Mastercam allows for fast and easy development of tool paths. 3)Fast and easy translation between CAD and CAM files. 4)You can check your work for errors before the actual machining began, saving the time and money. King Saud University Industrial Engineering Department

Manufacturing Process The dimensions of the femur of the artificial knee joints were measured to get the following dimensions:

Procedure of Manufacturing 1) The blank for the job is prepared by Material cutting, milling and surface grinding. 2) The workpiece is WIRECUT in the WEDM machine and so is the holder 3) The workpiece is machined in the upside- down direction to finish all bottom operations with material for a screw hole in the center King Saud University Industrial Engineering Department

Procedure of Manufacturing 4) The workpiece is fixed to the holder with the screw. The job is held at 45degree to run a CAM program generated in that direction. 5) The workpiece is than held at another angle of -45degree to run another CAM program generated in that direction. 6) The job is polished to achieve the required finish King Saud University Industrial Engineering Department

Final Shape King Saud University Industrial Engineering Department

Machine The machine used to manufacture this artificial femur knee joint was a Huron kx-15 five axis machine That device is very appreciated for the machining of very technical and complex work pieces King Saud University Industrial Engineering Department

CNC Controller CNC stands for "Computer Numeric Control". It's referring to machinery that is under automated control, as opposed to manually by an operator.``` King Saud University Industrial Engineering Department

G-Codes What is G-code? When the designed product is produced using CNC machine tools, the machine tool controller needs explicit instructions describing the type and order of individual steps required to perform a given task. These instructions are provided to the controller in the form of alphanumeric codes (G-code) and are usually called a part program. King Saud University Industrial Engineering Department

Sample of G-Codes % (PROGRAM NAME - Knee joint) N100G21 N102G0G17G40G49G80G90 (UNDEFINED TOOL - 1 DIA. OFF LEN. - 1 DIA. - 6.) N104T1M6 N106G0G90G54X Y2.758A0.S50M5 N108G43H1Z60. N110Z-.354 N112G1Z-5.354F0. N114X Z N116X Z N118X Z-4.66 N120X Z-4.24 N122X Z N124X Z N126X Z N128X Z N130X Z N132X Z N134X Z King Saud University Industrial Engineering Department

Sample of G-Codes N1178X-37.64Z-7.54 N1180X Z N1182X Z N1184X Z N1186Z N1188G0Z N1190X Y N1192G1Z N1194Z N1196X Z N1198X Z-8.59 N1200X Z N1202Z N1204G0Z-3.84 N1206X N1208G1Z N1210Z N1212X Z N1214X Z-8.59 N1216X Z N1218Z N1220M5 N1222G91G0G28Z0. N1224G28X0.Y0.A0. N1226M30 % King Saud University Industrial Engineering Department

Tool path for the model Video of Process 1 st set up 2 nd set up King Saud University Industrial Engineering Department

Conclusions The present work shows that artificial knee joint could be manufactured locally. The MasterCAM proved sufficient, not only to represent the femur part of the joint, but also to generate tool path and G-codes necessary to manufacture the femur part of the joint. This success will hopefully have a reflection on the manufacture of custom-made artificial knee. This is expected to help reduce the suffering of our patients. King Saud University Industrial Engineering Department

Thank You … King Saud University Industrial Engineering Department Special thanks to my adviser Prof. Darwish