A biomechanical model of stand-up wheelchairs

Stand-up wheelchairs are becoming more popular among clinicians and consumers. This is due to the expected physiological, psychological and functional benefits of stand-up wheelchairs. However, little is known about the biomechanical and clinical aspects of stand-up wheelchairs. This poses a substantial risk to stand-up wheelchair users. This paper presents a model for examining knee forces, knee-block forces, seat shear forces, and backrest shear forces. The model shows that substantial forces can occur at the user's knee and wheelchair's knee-block. These forces must be properly aligned and distributed to prevent injury to the structures of the knee and lower leg.