Synovial joint is a joint, which is placed between bones and enclosed in a capsule of thick slippery liquid called synovial fluid. These joints are articulated to move freely between bones. These are widely used in medical applications when joints between bones are broken or damaged due to some other reasons. There are structural and functional defects that will distinguish synovial joint and natural joint such as strength, durability and lubricity. Owing to these defects in the knee joint forces like knee contact force, muscle cocontraction and ligament forces are increasing and causing damage to the knee joint. Many people are suffering with joint diseases and other types such as bone fracture and to mitigate it a mechanical component is designed to replace the knee joint. Therefore, the stress distribution on various knee joint designs is performed and discussed on various defects that affect it so that the possible defects can be reduced. Copyright © 2015 Inderscience Enterprises Ltd.