Photo: Arek Adeoye/Unsplash
New Delhi: Limb disability is a serious malady and is caused by a number of reasons including age-related ailments, physical deformations, accidents, strokes and polio. According to Census 2011, there are five million people with locomotor disabilities in India alone.
Lower limb rehabilitation, especially for gait recovery, is faced with several problems. Among other things, it is time consuming and there are not enough therapists to meet the demands particularly in the context of increasing population of the aged. Efforts are underway to design robotic devices that would help automate rehabilitation.
Many robotic systems are now available. However, most of them are able to treat the patients by performing motions in only one plane – the sagittal plane, which is an imaginary plane that divides the body into the left and right parts. For complete limb movement, flexibility in transverse (upper and lower body) and coronal (front and back) planes is also essential.
A new study, conducted by a joint team of researchers from IIT Jodhpur, IIT Palakkad, the French National Centre for Scientific Research (CNRS) and the Belgorod State Technological University, Russia, promises to fill the gap.
They have proposed a robot manipulator arrangement that is capable of providing motion in all the three planes. The usefulness of the design was tested and confirmed with the help of computer-based simulations along with a motion control scheme by performing various clinically suggested therapeutic passive range of motions.
The design could execute important essential rehabilitation therapeutic movements like abduction (the motion of a limb or appendage away from the midline of the body), adduction (the motion of a limb or appendage towards the midline of the body), flexion (bending movement), and extension of the hip and knee joints.
“The robotic trainer we have designed will help providing physiotherapy to paralytic patients, and for those who have spinal cord injuries that have disrupted their lower limb functions,” Jayant Kumar Mohanta, an assistant professor in the department of mechanical engineering, IIT Jodhpur, and the research leader, said.
The trainer, he noted, is conceptually simple and has a modular mechanical configuration that is easy to fix and use. Besides, it can help perform rehabilitation therapies for lower limb at the knee as well as hip joints in sitting/lying positions. The design ensured a large workspace to execute the required range of motion therapies, he added.
“Innovative robotics for rehabilitation is certainly a need of the hour to address the gap between the availability of therapists and the number of people who need rehabilitation,” Sujatha Srinivasan, a professor at the T.T.K. Center for Rehabilitation Research and Device Development, IIT Madras, who was not part of the study, said. “I look forward to the design being realised as a physical prototype, tested with therapists and users, and eventually put to clinical use.”
Sunderarajan Padmanabhan is a science journalist. He tweets at @ndpsr.