GAIT BIOMECHANICS IN NORMAL CONDITIONS AND WITH A LOWER-EXTREMITY PROSTHESIS CAPTURED BY THE Xsens SYSTEM

Abstract

Aim. To compare kinematics between normal conditions and a lower-extremity prosthesis by using the Xsens motion capture system. Materials and methods. Two volunteers with similar anthropo­metry participated in the study: one apparently healthy individual weighing 78.1 kg and another weighing 67 kg without the prosthesis. A gait assessment was undertaken on the Life Fitness treadmill, covering a distance of 100 meters at a speed of 3 km/h. Heart rate measurements were obtained at baseline and immediately after exercise. Results. Walking with the prosthesis on the treadmill at a speed of 3 km/h resulted in 28.5 % more vertical pelvic oscillations and a greater variety of vertical pelvic accelerations. In a volunteer with prosthesis, walking at a distance of 100 meters resulted in an increase in HR of 22 bpm (from 74 to 96 bpm). The results obtained along with kinematic walking data show a significantly higher energy cost compared to walking in normal conditions. Conclusion. Based on the data obtained with the Xsens motion capture system and a calculated segmental body mass, the method was developed, and maximal efforts in contact areas on the treadmill were measured along with the energy cost of HR modulation. As soon as the CoM is located in the pelvis area, a pelvis sensor is recommended for further studies to provide a timely assessment of changes. This makes numerical differentiation unnecessary, as the Xsens system provides it automatically for all body segments.