Introduction The human foot and ankle is composed of 26 bones, 33 joints, and more than one hundred muscles, tendons, and ligaments. These components work together to provide the body with support, balance and mobility. The foot acts as a “rigid lever and mobile adapter” (Amstrong [Prosthetic foot], 2010). The human foot must be able to support the weight of the body and function as a shock absorber (Swierzewski, 2007; NYU, 1990). The prosthetic foot must be able to mimic the missing natural foot, to achieve a more efficient walking pattern. When a natural foot is missing due to disease, accident, or developmental malformation, a prosthetic foot is used to mimic the missing limb in an attempt to create the most efficient gait pattern. The prosthetist must choose between numerous types of prosthetic feet, depending on the patient's physical condition and lifestyle needs (Swierzewski, 2007). Gait Cycle The human gait cycle is composed of multiple sequential steps. It begins with the heel of the foot touching the ground and ends when the same foot touches the ground again (Perry, 1992). The period of the gait cycle in which the foot is on the ground is called the stance phase. The period in which the foot is in the air is called the swing phase. The phases of the gait cycle are initial contact (IC), load response (LR), mid stance (MSt), terminal stance (TSt), preswing (PSw), initial swing (ISw), mid stance (MSw), and swing terminal (TSw). There are three main functions of the gait cycle, which are weight acceptance, single limb support and limb advancement. Weight acceptance occurs during initial contact and response to load. During these phases, the limb is stabilized to prevent falls and the foot enjoys... middle of paper... activity. The main disadvantage of this foot is that it costs more than other feet and can only be used by patients at the K3 level or above (Lusardi & Nielsen, 2007).ManufacturersThere are several manufacturers of prosthetic feet such as Ossur, Ottobock, Ohio Willow Wood and SPS. Most companies specialize in adult feet, although there are some manufacturers like Ossur that have a special pediatric line. On company websites, feet are organized by K-level and further classified by male or female. Prosthetic feet are available in different lengths in centimeters and left or right. They are also grouped based on the weight of the patient who can use the foot safely. Some feet come in different colors of leather and others have a space between the big toe and second toe to accommodate the user who wishes to wear flip flops or shoes with toe straps.