Issues and Challenges of Rehabilitation Robots for the Lower Limb and the Importance of Trunk Control Integration

With advantages in accuracy and reliability, the use of rehabilitation robots is already being used for instances such as stroke or post-surgical rehabilitation, which mainly uses lower limb rehabilitation. However, lower limb muscles are not the only muscles involved in lower limb activities. Trunk muscles are vital in supporting the body while performing functional activities like standing, sitting, and walking. Despite its importance, this is rather a neglected area of lower limb rehabilitation robots. Previous studies in stroke rehabilitation were focused on the upper and the lower extremities. The paper summarizes the most known and recent research of lower-limb rehabilitation robots and how trunk muscles are often missed out. In addition, various tools for measuring trunk performance, stability, or control were presented. Lastly, the importance of integrating trunk control in lower limb rehabilitation devices was discussed.