Improvement of non-invasive semi-automatic test device for measurement of finger joints range of motion: Reduction in burden on therapist

When measuring the range of motion (ROM) of finger joints, a therapist usually uses a goniometer, which is a measuring instrument for angles. However, a measurement with a goniometer takes much time, because there are many joints in a hand. To solve this problem, we aim to develop a non-invasive automatic test device in order to reduce the burden on patients and therapists when measuring the ROM of finger joints. In our previous work, we developed a semi-automatic test device for reducing the burden on the patient. In this study, we aim to reduce the burden on the therapist by improving the conventional goniometer device. The improvement points include an increase in the visibility of target joints, an increase of operability of the virtual goniometer, and a reduction of the startup program execution time. We compared the required time to measure the angle of a PIP joint of the conventional goniometer device and the proposed goniometer device. As a result, the required time was reduced, which means a reduction in the burden on the therapist. Moreover, we evaluated the measurement accuracy by testing the proposed goniometer device and comparing the results with a conventional goniometer. The obtained result shows that the measurement accuracy of the proposed goniometer device was less than 6.6°.