The Influence of Transtibial Prosthesis Type on Lower-Body Gait Adaptation: A Case Study.

Gait parameters are altered and asymmetrical in individuals with transtibial amputation. The purpose of this study was to evaluate and compare the effect of four different prosthetic feet on lower-limb biomechanics during gait. A 34-year-old man with transtibial amputation performed four gait analysis sessions with four foot-ankle prostheses (Variflex, Meridium, Echelon, and Kinterra). Kinematic and kinetic parameters and gait symmetry were analyzed in different prosthetic conditions. The type of prosthesis had little effect on the participant's spatiotemporal parameters. Throughout the stance phase, increased hip angle, reduced knee flexion and ankle dorsiflexion were observed in the amputated leg. For kinetic parameters, reduced propulsive force (SI = 0.42-0.65), reduced knee extension moment (mainly during Echelon and Kinterra conditions, SI = 0.17 and 0.32, respectively), and increased knee abduction moment (mainly during the Variflex and Meridium, SI = 5.74 and 8.93, respectively) were measured in the amputated leg. Lower support moments were observed in the amputated leg as compared to the unaffected leg, regardless of the type of prosthesis (SI = 0.61-0.80). The prostheses tested induced different lower-limb mechanical adaptations. In order to achieve the clinical goal of better gait symmetry between lower limbs, an objective gait analysis could help clinicians to prescribe prosthetic feet based on quantitative measurement indicators to optimize gait rehabilitation.