Total Knee Arthroplasty (TKA) is an effective mean to relieve extreme pain and for restoring normal knee functionality in patients. In TKA procedure, a surgery is performed in the knee joint that helps thousands of patients around the world who are afflicted with arthritis or other debilitating diseases of the knee joint. There exist about ten types of the prosthesis due to variation in patient's knee size, its geometry and the type of defects. Thus, implants customization is highly desired in order to provide custom-fit implants that fit perfectly on patient knee joints. To enhance production of patient-specific implants, this study proposed a fully integrated method of converting 2D Magnetic Resonance Imaging (MRI) to a 3D Computer-Aided-Design (CAD) file automatically for downstream manufacturing process such as Computer-aided Manufacturing. In this research, the 2D MRI image is converted to a CAD system readable file format using mathematical and image processing method. The result of this study presented an automatic image converting system capable of rapid image conversion that would ultimately contribute to the customised medical knee implant leading to help society and medical community. © 2015 American Scientific Publishers All rights reserved.