Ground reaction forces during stair climbing in transfemoral amputation - a case study

Conducting a gait analysis allows us to make an accurate diagnosis to document the progress of rehabilitation, as well as properly adapt the prosthesis to the patient. This study focuses on examinating the differences between a choosen healthy person (OZ) and a choosen person after an amputation (OPA) with enucleation in the knee joint in case of climbing stairs (ascent and descent). Two male volunteers of similar age (20-22 years) and height (180-185 cm) participated in the study. Biomechanical analysis was carried out using three prosthetic sets differing in knee joints (1. Blatchford Mercury, 2. Guardian, 3. Ottobock 3R80) and prosthetic foot (1. Össur Vari-Flex XC Rotate, 2. SACH, 3. Blatchford Elite 2). The staircase consisted of four steps (height 170mm, width 320mm). During the experiment, an optoelectronic motion capture system and force plate were used. Obtained results showed limited efficiency of ascending and descending stairs by OPA, compared to OZ. The most important difference between a healthy person and an amputee is their gait pattern, step-over-step and step-by-step gait, respectively. The value of the vertical component of the ground reaction force when climbing stairs is similar for both subjects. The analyzed parameters differ depending on the prosthetic set used by OPA. During the descent, the OPA can implement the step-over-step pattern, but only using the prosthesis set I (everyday use). Then, the forces acting on the sound limb during the stance phase are much higher than for OZ, which creates the possibility of overloading the given limb. The conducted biomechanical analysis draws attention to the importance of proper selection of the prosthesis for the patient.