A study published online July 25 in Prosthetics and Orthotics International explored gait differences across different surface conditions for individuals with transfemoral amputations and K-3 or K-4 activity levels.
Ten people with transfemoral amputations, four at K-3 and six at K-4, and ten matched individuals without amputations walked in a virtual environment with simulated level and nonlevel surfaces on a self-paced treadmill. Stability measures included the medial-lateral margin of stability, step parameters, and gait variability (standard deviations for speed, temporal-spatial parameters, root-mean-square of medial-lateral trunk acceleration).
Study results showed that those with a K-3 level of mobility walked slower than K-4 individuals with wider steps, greater root-mean-square of medial-lateral trunk acceleration, and greater medial-lateral margin of stability standard deviations, indicating their stability was further challenged. In addition, K-3 participants had greater asymmetry in double support time and trunk acceleration root-mean-square in the medial-lateral direction, but similar asymmetry overall. K-3 participants also had larger differences from AB and in more parameters than K-4 individuals, although K-4 differed from AB in trunk acceleration root-mean-square in the medial-lateral direction, walking speed, and double support time standard deviations.