Biomechanical evaluation of a novel wheelchair backrest for elderly people

Background Back pain is a common complication of wheelchair-bound elderly people. Seating system is a key factor that influences spinal curvature, back muscle activation, interface pressure, and comfortability. A seating system can maintain lumbar lordosis, lower back muscle activity, and decrease ischial tuberosities pressure, which reduces spinal load and directly influences sitting comfort. Our previous study has confirmed that backward thoracic support showed a relatively higher lumbar lordosis and lower back muscle activity. This study intends to evaluate the influence of backward thoracic support on interface pressure and subjective discomfort.