Orthoses are externally applied devices used to modify the structural and functional characteristics of the neuromusculoskeletal systems; prostheses are externally applied devices used to replace, wholly or in part, an absent or deficient body segment. Included are, e.g. body-powered and externally powered external orthoses, prostheses, orthopaedic footwear. Excluded are endo-prostheses, which are not part of this document.

A collection of compatible components that can be integrated to produce a range of different lower limb prostheses. Included are, e.g. cosmetic lower limb prostheses.

Devices that replace part of the lower limb at the ankle joint after amputation or due to congenital limb deficiency