A Biomechanical Approach for Assessing Rheumatoid Arthritis Progression

Rheumatoid Arthritis (RA) is a chronic autoimmune condition that mainly affects the joints, leading to pain, stiffness, and deformities. Early identification and management are crucial for dealing with RA effectively and preventing irreversible joint damage. However, traditional disease progression tracking methods can be invasive and inaccessible, particularly in low-resource settings. This paper proposes a low-cost disease progression tracking system that measures stiffness in the Metacarpophalangeal (MCP) and Proximal Interphalangeal (PIP) joints and the ability of a patient to sustain grip, two key early indicators of RA. This system will feature a mechanical actuator that applies controlled angular flexion to the MCP and PIP joints at angles ranging from -30 ° to +60 °, an FSR - torque sensor combination to measure the resistive force exerted by the finger on it, and an angle sensor to measure the maximum angle to which the finger can be bent, all of which will help measure the joint stiffness. The device will also have a load cell that measures the force applied to calculate the grip strength.