Do Upper-Limb Loss and Prosthesis Use Affect Lower-Limb Gait Dynamics?

Introduction Intentional interruption of upper-limb and lower-limb coordination of able-bodied subjects alters their gait biomechanics. However, the effect of upper-limb loss (ULL) on lower-limb gait biomechanics is not fully understood. The aim of this secondary study was to perform a follow-up analysis of a previous dataset to characterize the spatiotemporal parameters and lower-limb kinematics and kinetics of gait for persons with ULL when wearing and not wearing an upper-limb prosthesis (ULP). We were particularly interested in quantifying the effects of matching the mass and inertia of the prosthetic limb to the sound limb. Materials and Methods Ten persons with unilateral ULL walked at a self-selected speed under three randomly presented conditions: 1) not wearing a prosthesis; 2) wearing their customary prosthesis; and 3) wearing a mock prosthesis that can be adjusted to match the length, mass, and inertial properties of each subject's sound limb. Walkway-embedded force plates and a 12-camera digital motion capture system recorded ground reaction forces (GRFs) and retroreflective marker position data, respectively. Average spatiotemporal (walking speed, cadence, stance time, swing time, step length, double support time), lower-limb kinematic (joint angles), and lower-limb kinetic (ground forces, joint moments and powers) data were processed, and their statistical significance values were analyzed. Result Walking speed for each condition was nearly equivalent (1.20 ± 0.01 m/s), and differences between condition were nonsignificant (P = 0.769). The interaction effect (side × prosthesis) was significant for peak hip extension (P = 0.01) and second peak (propulsive) vertical GRF (P = 0.028), but separate follow-up analyses of both main effects were not significant (P ≥ 0.099). All other main effect comparisons were not significant (P ≥ 0.102). Conclusions Although the sample cohort was small and heterogeneous, the results of this study suggest that persons with unilateral ULL did not display significant limb side asymmetry in lower-limb gait spatiotemporal, kinetic, and kinematic parameters, regardless of ULP use.