Prosthesis; Prosthetic device: Externally applied device used to replace wholly, or in part, an absent or deficient limb segment. (จากข้อ 2.1.1 ใน ISO 8549-1 : 1989)
Orthosis; Orthotic device: Externally applied device used to modify the structural and functional characteristics of the neuro-muscular and skeletal systems. (จากข้อ 2.1.2 ใน ISO 8549-1 : 1989)