The lower limb prosthesis consists of four main components: the socket, suspension system, lower limb connection, artificial foot, and ankle. It not only needs to meet aesthetic requirements but also functional demands for walking. Depending on specific design, it can be classified into various types such as static ankle-foot, single-axis foot, and multi-axis foot.

In the classification, there are two main types:

1. Shell prostheses (also known as exoskeletal limb prostheses): These use a shell to bear the load, and the shape of the shell resembles the human limb. They are typically made from materials like fiberglass, carbon fiber, aluminum, or polyethylene sheets, with aluminum, polyethylene, or carbon fiber being common choices.
 
2. Frame prostheses (also known as endoskeletal prostheses or modular prostheses): These consist of metal or plastic pipes connecting the socket, artificial foot, and ankle, with all pressure being transmitted through the connecting pipes.