Researchers in the United Kingdom evaluated differences in gait outcomes between people with unilateral transfemoral amputations and concluded that the magnitude of the effect sizes of gait deviations support the need for continued efforts to improve prosthetic equipment and rehabilitation services for this population.
Using a cross-sectional study design, the level, overground gait of 60 established transfemoral prosthesis users with mechanical knee joints were compared with that of ten able-bodied people. Gait profile score, walking velocity, step length, step length symmetry ratio, step time symmetry ratio, vertical ground reaction force symmetry index, base of support, center of mass deviation, and metabolic energy expenditure were measured. The prevalence of gait deviations for each participant with a transfemoral amputation was assessed by inspection, using a predefined list of lower-limb kinematic, upper-body kinematic, ground reaction force, and lower-limb kinetic gait deviations.
The research team found statistically significant between-group differences across all outcome measures. The most prevalent gait deviations included the lack of prosthetic knee flexion in early stance (98 percent); lack of hip extension on the prosthetic side in late stance (82 percent); increased trunk side flexion range of motion across the gait cycle (92 percent); reduced anterior propulsion force on the prosthetic side in late stance (100 percent); and reduced prosthetic hip adduction moment in early stance (96 percent).
The prosthesis users’ gait patterns were characterized as walking with slow speed, reduced step length, asymmetries in step length and step time, wide base of support, asymmetry in vertical ground reaction force, and ultimately an increased energy cost of walking. According to the study’s authors, the results indicate that the magnitude of the differences between people with unilateral transfemoral amputations and able-bodied people are such that significant research into all aspects of prosthetic rehabilitation to reduce these differences is clearly justified.
“While it is far from surprising that [unilateral transfemoral] participants did not walk as well as healthy unimpaired adults, the between-group differences were all statistically significant and the magnitude of the effect sizes, ranging from ‘large’ to ‘huge’, are noteworthy,” wrote the authors.
The open-access study was published in Gait & Posture.
