Fig. 2
From: Sensor-assessed grasping time as a biomarker of functional impairment in rheumatoid arthritis

Exemplary data of one rheumatoid arthritis patient for the task flexion interphalangeal joints. (a) Absolute distal interphalangeal (DIP) joint flexion angle (degree positive for flexion) for all four fingers. (b) Absolute proximal interphalangeal (PIP) joint flexion angle for all fingers. (c) Measured values (blue dots) for the ratio between DIP/PIP joint angles (0.62) and linear regression (in red) for the calculation of r-squared (R2) (0.99) for the index finger.