ABSTRACT: Exhibited in the Egyptian Galleries in the British Museum (London, UK) is an exquisitely crafted artificial big toe for the right foot. It is made from cartonnage, a type of paper mache (layers of linen soaked with animal glue and coated with tinted plaster), and has been dated to before 600 BC. Distinct signs of wear prompted one researcher to call it “one of the earliest working prostheses to have been identified from the ancient world.” Housed in the Egyptian Museum (Cairo, Egypt) is a second example found strapped onto the right foot of a female mummy and dated to between 950 and 710 BC. Made in three pieces, it has a complex series of laces that joins the three sections together. To date, this artifact may be the oldest known intravital limb prosthesis in existence. The objective of this research was to assess the functionality of their design. Design replicas (P1 and P2, respectively) were made and assessed using two volunteers (V1 and V2) exhibiting complete disarticulation at the first metatarsophalangeal joint of the right foot. Computerized gait analysis evaluated selected gait parameters against their sound left side (control). Foot kinematic and kinetic data were recorded (average of 10 trials), plus a volunteer questionnaire was completed. Kinematic data from both replicas demonstrated a very satisfactory level of relative dorsiflexion, especially for V1, when worn with an Egyptian-style sandal (87.13% of the normal average range). Kinetic data showed no significant increase in plantar pressures between the affected and the sound side when worn with or without a sandal. However, when the volunteers wore sandals without the toe prosthesis, significant differences in peak pressures were recorded, indicating a potential benefit of P1 and P2 when wearing Egyptian sandals. Both volunteers indicated in the questionnaire that P2 was the more comfortable of the two. This research concluded that although both devices could have afforded at least limited ambulation, the performance and perceived comfort of the three-part wooden replacement infers that nascent prosthetic science may have been emerging in the Nile Valley as early as 950 to 710 BC.