1287 JRRD JRRD Volume 51, Number 8, 2014 Pages 1287–1296 Does unilateral transtibial amputation lead to greater metabolic demand during walking? Elizabeth Russell Esposito, PhD; 1–2* Kelly M. Rodriguez, MS; 1 Christopher A. Ràbago, PT, PhD; 1–2 Jason M. Wilken, PT, PhD 1–2 1 Center for the Intrepid, Department of Orthopaedics and Rehabilitation, Brooke Army Medical Center, Fort Sam Houston, TX; 2 Department of Defense-Department of Veterans Affairs Extremity Trauma and Amputation Center of Excellence Abstract—Previous literature reports greater metabolic demand of walking following transtibial amputation. However, most research focuses on relatively older, less active, and often dysvascular amputees. Servicemembers with traumatic ampu- tation are typically young, fit, and highly active before and often following surgical amputation of their lower limb. This study compared the metabolic demand of walking in young, active individuals with traumatic unilateral transtibial amputa- tion (TTA) and nondisabled controls. Heart rate (HR), rate of oxygen consumption, and rating of perceived exertion (RPE) were calculated as subjects walked at a self-selected velocity and at five standardized velocities based on leg length. The TTA group completed a Prosthetics Evaluation Questionnaire. Oxygen consumption (p = 0.89), net oxygen consumption (p = 0.32), and RPE (p = 0.14) did not differ between groups. Com- pared with controls, HR was greater in the TTA group and increased to a greater extent with velocity (p < 0.001). Overall, the TTA group rated their walking abilities as high (mean: 93% out of 100%). This is the first study to report equivalent meta- bolic demand between persons with amputation and controls walking at the same velocity. These results may reflect the physical fitness of the young servicemembers with traumatic amputations and may serve to guide outcome expectations in the future. Key words: amputee, energetics, gait, heart rate, military, oxy- gen consumption, prosthetic, servicemember, speed, traumatic. INTRODUCTION It is widely accepted that individuals with a transtib- ial amputation (TTA) have greater metabolic demands during walking than nondisabled nonamputees. At simi- lar walking speeds, metabolic demand for individuals with unilateral TTA is 9–33 percent greater [1–7] than nondisabled individuals and can influence rehabilitation, prosthetic prescription, and patient participation in daily physical activities. Those with TTA appear to compen- sate for the increase in energy expenditure by adopting self-selected walking speeds 7–42 percent slower than nondisabled individuals [4,8–9]. Walking slower allows them to achieve equivalent metabolic rates as nondis- abled individuals [2,10], potentially to limit physical exertion [6]. The end result, however, is a 14 percent greater total metabolic cost to walk an equivalent dis- tance to nondisabled individuals [8]. Abbreviations: AVO 2 = arterio-venous difference, FR = Froude, HR = heart rate, PEQ = Prosthetics Evaluation Ques- tionnaire, RPE = rating of perceived exertion, SSWV = self- selected walking velocity, TTA = transtibial amputation, VO 2 = rate of oxygen consumption. * Address all correspondence to Elizabeth Russell Esposito, PhD; 3551 Roger Brooke Dr, Center for the Intrepid, Fort Sam Houston, TX 78234; 210-539-5824. Email: Erussell.kin@gmail.com http://dx.doi.org/10.1682/JRRD.2014.06.0141