Comparative Effectiveness of Microprocessor Controlled and Carbon Fiber Prosthetic Feet in Transtibial Amputees

Inclusion Criteria: * Unilateral transtibial amputation * Age 18-99 years old * Body weight below 275 lbs * Non-pregnant * English speaking * Current user of prosthesis for at least one year * Wear time 8 hrs/day or more * MFCL ≥ K-3 * Well-fitting and functioning prosthesis * No use of ambulatory aide * Able to tolerate testing protocol * Able to walk on slopes * Must, in the opinion of the investigator, be willing and able to complete all aspects of the study, adhere to the study visit schedule and comply with the assessments Exclusion Criteria: * Amputation level other than unilateral transtibial * Age \<18 or \>99 years old * Body weight above 275 lbs * Pregnant * Non-English speaking * Not current user of prosthesis * Less than one year use of prosthesis * Wear time less than 8 hr/day * MFCL \<K3 * Poor fitting and functioning prosthesis * Indicating that the socket fit is painful, or unacceptable * Use of ambulatory aide * Unable to tolerate testing protocol * Unable to walk on slopes * Presence or history of any condition that, in the view of the investigator, places the participant at high risk of poor treatment compliance or of not completing the study * Any neurologic impairments known to cause gait and/or balance dysfunction