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.

Orthoses designed to modify the structural and functional characteristics of the neuromusculoskeletal systems of the lower limb; the devices may be custom fabricated or prefabricated; the prefabricated devices may be adjustable or ready to use

Orthoses that encompass the lumbar regions of the trunk, the hip, knee and ankle joints and the foot, with or without the thoracal part of the spine