Approximately 82 percent of all amputations performed in the United States are transtibial amputations, in which the leg is removed below the knee. Because the knee joint is left intact the use of prosthetics is one of the most preferred methods for returning mobility to amputees. The improvement of prosthetics for transtibial amputees is currently an area of intense research. This paper summarizes the state of the art of prosthetics for transtibial amputees by focusing on the four major components associated with standard transtibial prosthetic. The socket transfers the forces between the residual limb and the prosthetic. A suspension system ensures that solid contact is maintained between the leg and the artificial limb. The prosthetic foot is attached to the socket by a pylon, which also accounts for length of limb lost during amputation. Prosthetic feet come in many forms ranging from little more than wooden blocks to carbon fiber sprinting feet. Two recent advances in transtibial prosthetics include the procedures of direct skeletal attachment, and distal tibiofibular bone bridging which increases the weight bearing capability of the residual limb.